Zodiac Killer Ciphers Wiki - User contributions [en]

Encyclopedia of observations

2026-02-09T12:17:35Z

Admin: /* Z408 and Z340 */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
** [https://forum.zodiackillerciphers.com/community/postid/4816/ Working link]
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]
* Excluding the 18-character "filler" or unsolved portion, the Z408 plaintext contains exactly 100 words. [https://discord.com/channels/1260505612131897375/1261206941275783281/1451744229939482738 (Source: 60thfever)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve (broken)]) [https://forum.zodiackillerciphers.com/community/postid/71367/ (fixed)]

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]
* Z340's alphabet consists of 63 unique symbols. Coincidentally, the lengths of Z18, Z13, and Z32 add up to 63. (source: @rogerverreault8682 on YouTube)

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* The frequencies of unique sequence lengths peaks at 17 with 26 repeats. [https://forum.zodiackillerciphers.com/community/postid/50355/ (Source)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.
* 9 out of 14 of the plaintext letters forming the pivots involve the letters A, E, or N. In both the 340 and 408 keys, the backwards L symbol decodes to A, the N symbol decodes to E, and the D symbol decodes to N. Those are the only symbols that decode to the same letter. Also, Z13 begins with the same three letters: AEN. [https://www.reddit.com/r/ZodiacExtortion/comments/1f3hqsl/pivot_patterns_with_aen_symbols/ (Source: Sam Fisher)]

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]
* If you count the letters in "life is" and the shifted letters "ratenyrnosrvs", they add up to 19 (the period required to transpose the plaintext) (Source: @timpsensky5181 on YouTube)
* The accompanying card has 13 lines plus 6 underlines = 19 total (not including "Des July Aug Sept Oct = 7" written under the crosshairs). Is this a hint to the period 19 scheme of Z340? (source: @trashlie on YouTube)

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])
* 17,20,24,340 and 408 are "[https://en.wikipedia.org/wiki/Evil_number evil numbers]". (Source: Jarl)
* Similar placement of "WILL BE" and "PARADICE" in the Z408 and Z340 plaintexts. ([https://discord.com/channels/1260505612131897375/1261206941275783281/1469068929216286915 Source: SolidSnake1990])

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Encyclopedia of observations

2026-02-04T16:09:35Z

Admin: /* Z408 and Z340 */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
** [https://forum.zodiackillerciphers.com/community/postid/4816/ Working link]
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]
* Excluding the 18-character "filler" or unsolved portion, the Z408 plaintext contains exactly 100 words. [https://discord.com/channels/1260505612131897375/1261206941275783281/1451744229939482738 (Source: 60thfever)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve (broken)]) [https://forum.zodiackillerciphers.com/community/postid/71367/ (fixed)]

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]
* Z340's alphabet consists of 63 unique symbols. Coincidentally, the lengths of Z18, Z13, and Z32 add up to 63. (source: @rogerverreault8682 on YouTube)

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* The frequencies of unique sequence lengths peaks at 17 with 26 repeats. [https://forum.zodiackillerciphers.com/community/postid/50355/ (Source)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.
* 9 out of 14 of the plaintext letters forming the pivots involve the letters A, E, or N. In both the 340 and 408 keys, the backwards L symbol decodes to A, the N symbol decodes to E, and the D symbol decodes to N. Those are the only symbols that decode to the same letter. Also, Z13 begins with the same three letters: AEN. [https://www.reddit.com/r/ZodiacExtortion/comments/1f3hqsl/pivot_patterns_with_aen_symbols/ (Source: Sam Fisher)]

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]
* If you count the letters in "life is" and the shifted letters "ratenyrnosrvs", they add up to 19 (the period required to transpose the plaintext) (Source: @timpsensky5181 on YouTube)
* The accompanying card has 13 lines plus 6 underlines = 19 total (not including "Des July Aug Sept Oct = 7" written under the crosshairs). Is this a hint to the period 19 scheme of Z340? (source: @trashlie on YouTube)

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])
* 17,20,24,340 and 408 are "[https://en.wikipedia.org/wiki/Evil_number evil numbers]". (Source: Jarl)

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Encyclopedia of observations

2026-01-13T11:00:56Z

Admin: /* Observations related to the discovered plaintext and encipherment method */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
** [https://forum.zodiackillerciphers.com/community/postid/4816/ Working link]
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]
* Excluding the 18-character "filler" or unsolved portion, the Z408 plaintext contains exactly 100 words. [https://discord.com/channels/1260505612131897375/1261206941275783281/1451744229939482738 (Source: 60thfever)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve (broken)]) [https://forum.zodiackillerciphers.com/community/postid/71367/ (fixed)]

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]
* Z340's alphabet consists of 63 unique symbols. Coincidentally, the lengths of Z18, Z13, and Z32 add up to 63. (source: @rogerverreault8682 on YouTube)

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* The frequencies of unique sequence lengths peaks at 17 with 26 repeats. [https://forum.zodiackillerciphers.com/community/postid/50355/ (Source)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.
* 9 out of 14 of the plaintext letters forming the pivots involve the letters A, E, or N. In both the 340 and 408 keys, the backwards L symbol decodes to A, the N symbol decodes to E, and the D symbol decodes to N. Those are the only symbols that decode to the same letter. Also, Z13 begins with the same three letters: AEN. [https://www.reddit.com/r/ZodiacExtortion/comments/1f3hqsl/pivot_patterns_with_aen_symbols/ (Source: Sam Fisher)]

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]
* If you count the letters in "life is" and the shifted letters "ratenyrnosrvs", they add up to 19 (the period required to transpose the plaintext) (Source: @timpsensky5181 on YouTube)
* The accompanying card has 13 lines plus 6 underlines = 19 total (not including "Des July Aug Sept Oct = 7" written under the crosshairs). Is this a hint to the period 19 scheme of Z340? (source: @trashlie on YouTube)

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Encyclopedia of observations

2025-12-20T21:27:31Z

Admin: /* Kasiski Examination */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
** [https://forum.zodiackillerciphers.com/community/postid/4816/ Working link]
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]
* Excluding the 18-character "filler" or unsolved portion, the Z408 plaintext contains exactly 100 words. [https://discord.com/channels/1260505612131897375/1261206941275783281/1451744229939482738 (Source: 60thfever)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve (broken)]) [https://forum.zodiackillerciphers.com/community/postid/71367/ (fixed)]

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]
* Z340's alphabet consists of 63 unique symbols. Coincidentally, the lengths of Z18, Z13, and Z32 add up to 63. (source: @rogerverreault8682 on YouTube)

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* The frequencies of unique sequence lengths peaks at 17 with 26 repeats. [https://forum.zodiackillerciphers.com/community/postid/50355/ (Source)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.
* 9 out of 14 of the plaintext letters forming the pivots involve the letters A, E, or N. In both the 340 and 408 keys, the backwards L symbol decodes to A, the N symbol decodes to E, and the D symbol decodes to N. Those are the only symbols that decode to the same letter. Also, Z13 begins with the same three letters: AEN. [https://www.reddit.com/r/ZodiacExtortion/comments/1f3hqsl/pivot_patterns_with_aen_symbols/ (Source: Sam Fisher)]

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]
* If you count the letters in "life is" and the shifted letters "ratenyrnosrvs", they add up to 19 (the period required to transpose the plaintext) (Source: @timpsensky5181 on YouTube)

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Encyclopedia of observations

2025-12-20T21:20:53Z

Admin: /* Other observations */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
** [https://forum.zodiackillerciphers.com/community/postid/4816/ Working link]
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]
* Excluding the 18-character "filler" or unsolved portion, the Z408 plaintext contains exactly 100 words. [https://discord.com/channels/1260505612131897375/1261206941275783281/1451744229939482738 (Source: 60thfever)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve])

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]
* Z340's alphabet consists of 63 unique symbols. Coincidentally, the lengths of Z18, Z13, and Z32 add up to 63. (source: @rogerverreault8682 on YouTube)

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* The frequencies of unique sequence lengths peaks at 17 with 26 repeats. [https://forum.zodiackillerciphers.com/community/postid/50355/ (Source)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.
* 9 out of 14 of the plaintext letters forming the pivots involve the letters A, E, or N. In both the 340 and 408 keys, the backwards L symbol decodes to A, the N symbol decodes to E, and the D symbol decodes to N. Those are the only symbols that decode to the same letter. Also, Z13 begins with the same three letters: AEN. [https://www.reddit.com/r/ZodiacExtortion/comments/1f3hqsl/pivot_patterns_with_aen_symbols/ (Source: Sam Fisher)]

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]
* If you count the letters in "life is" and the shifted letters "ratenyrnosrvs", they add up to 19 (the period required to transpose the plaintext) (Source: @timpsensky5181 on YouTube)

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Encyclopedia of observations

2025-12-16T21:17:07Z

Admin: /* Other observations */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
** [https://forum.zodiackillerciphers.com/community/postid/4816/ Working link]
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve])

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]
* Z340's alphabet consists of 63 unique symbols. Coincidentally, the lengths of Z18, Z13, and Z32 add up to 63. (source: @rogerverreault8682 on YouTube)

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* The frequencies of unique sequence lengths peaks at 17 with 26 repeats. [https://forum.zodiackillerciphers.com/community/postid/50355/ (Source)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.
* 9 out of 14 of the plaintext letters forming the pivots involve the letters A, E, or N. In both the 340 and 408 keys, the backwards L symbol decodes to A, the N symbol decodes to E, and the D symbol decodes to N. Those are the only symbols that decode to the same letter. Also, Z13 begins with the same three letters: AEN. [https://www.reddit.com/r/ZodiacExtortion/comments/1f3hqsl/pivot_patterns_with_aen_symbols/ (Source: Sam Fisher)]

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]
* If you count the letters in "life is" and the shifted letters "ratenyrnosrvs", they add up to 19 (the period required to transpose the plaintext) (Source: @timpsensky5181 on YouTube)

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Encyclopedia of observations

2025-12-16T21:16:45Z

Admin: /* Other observations */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
** [https://zodiackillersite.com/viewtopic.php?p=84668#p84668 Working link]
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve])

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]
* Z340's alphabet consists of 63 unique symbols. Coincidentally, the lengths of Z18, Z13, and Z32 add up to 63. (source: @rogerverreault8682 on YouTube)

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* The frequencies of unique sequence lengths peaks at 17 with 26 repeats. [https://forum.zodiackillerciphers.com/community/postid/50355/ (Source)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.
* 9 out of 14 of the plaintext letters forming the pivots involve the letters A, E, or N. In both the 340 and 408 keys, the backwards L symbol decodes to A, the N symbol decodes to E, and the D symbol decodes to N. Those are the only symbols that decode to the same letter. Also, Z13 begins with the same three letters: AEN. [https://www.reddit.com/r/ZodiacExtortion/comments/1f3hqsl/pivot_patterns_with_aen_symbols/ (Source: Sam Fisher)]

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]
* If you count the letters in "life is" and the shifted letters "ratenyrnosrvs", they add up to 19 (the period required to transpose the plaintext) (Source: @timpsensky5181 on YouTube)

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Encyclopedia of observations

2025-12-14T16:30:45Z

Admin: /* Repeated symbols by columns and rows */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve])

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]
* Z340's alphabet consists of 63 unique symbols. Coincidentally, the lengths of Z18, Z13, and Z32 add up to 63. (source: @rogerverreault8682 on YouTube)

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* The frequencies of unique sequence lengths peaks at 17 with 26 repeats. [https://forum.zodiackillerciphers.com/community/postid/50355/ (Source)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.
* 9 out of 14 of the plaintext letters forming the pivots involve the letters A, E, or N. In both the 340 and 408 keys, the backwards L symbol decodes to A, the N symbol decodes to E, and the D symbol decodes to N. Those are the only symbols that decode to the same letter. Also, Z13 begins with the same three letters: AEN. [https://www.reddit.com/r/ZodiacExtortion/comments/1f3hqsl/pivot_patterns_with_aen_symbols/ (Source: Sam Fisher)]

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]
* If you count the letters in "life is" and the shifted letters "ratenyrnosrvs", they add up to 19 (the period required to transpose the plaintext) (Source: @timpsensky5181 on YouTube)

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Solution to the 340

2025-12-11T21:45:55Z

Admin: /* Saturday, January 3, 2015 */

== Raw text of the solution, after reversing transposition ==

''Presumed errors are in boldface:''

: I HOPE YOU ARE HAVING LOTS OF F'''A'''N IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRING'''O''' UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECA'''A'''SE IT WILL SEND ME TO PARAD'''L'''CE
: ALL THE SOO'''H'''ER BECAUSE '''E''' NOW HAVE ENOUGH SLAVES
: TO WOR'''V''' FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I '''V'''NOW THAT MY NEW
: LIFE IS LIFE WILL BE AN EASY ONE IN PARADICE DEATH

''With errors corrected:''

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE IS LIFE WILL BE AN EASY ONE IN PARADICE DEATH

== Interpretations of the seemingly misplaced words "LIFE IS" and "DEATH" ==

=== Group "LIFE IS" with "DEATH" ===

Example 1:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE WILL BE AN EASY ONE IN PARADICE.
: '''LIFE IS DEATH'''

Example 2:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE WILL BE AN EASY ONE IN PARADICE.
: '''DEATH IS LIFE'''

Example 3:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: '''LIFE IS DEATH'''. LIFE WILL BE AN EASY ONE
: IN PARADICE

Example 4:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH. '''LIFE IS DEATH'''. I AM NOT AFRAID
: BECAUSE I KNOW THAT MY NEW LIFE WILL BE AN EASY
: ONE IN PARADICE

Example 5:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE WILL BE AN EASY ONE: '''DEATH IS LIFE'''
: IN PARADICE.

''Additional speculation: The original ciphertext starts with the letters "HER", so perhaps the intended message formed from these fragments is "HER LIFE IS DEATH".''

=== Change "THAT" to "WHAT" ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW '''WHAT''' MY NEW
: LIFE IS: LIFE WILL BE AN EASY ONE IN PARADICE DEATH

=== "MY DEATH IS NEW LIFE" ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY
: '''DEATH IS NEW LIFE'''. LIFE WILL BE AN EASY ONE
: IN PARADICE

=== "WHERE DEATH IS LIFE" (suggested by Brandon Baskin) ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASNT ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME EVERYONE ELSE HAS NOTHING WHEN THEY
: REACH PARADICE SO THEY ARE AFRAID OF DEATH I AM
: NOT AFRAID BECAUSE I KNOW THAT MY NEW LIFE WILL
: BE AN EASY ONE IN PARADICE '''WHERE DEATH IS LIFE'''

=== "DEATH WILL BE AN EASY ONE" (suggested by @muzutus on YouTube) ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE IS LIFE IN PARADICE
: DEATH WILL BE AN EASY ONE

== Verifications of the solution ==

* FBI confirmations:
** [https://twitter.com/FBISanFrancisco/status/1337477701825925120 FBI statement on their twitter account]
** [https://www.cnet.com/science/zodiac-killer-message-known-as-340-cipher-solved-after-51-years/ Article with excerpt from more detailed FBI statement]
** The full press release that was sent to me from the FBI press office:
*** ''The FBI has a team of cryptanalysis experts that decipher coded messages, symbols, and records from criminals known as the Cryptanalysis and Racketeering Records Unit. CRRU regularly works with the cryptologic research community to solve ciphers. On December 5, 2020, the FBI received the solution to a cipher popularly known as Z340 from a cryptologic researcher and independently verified the decryption. Cipher Z340 is one of four ciphers attributed to the Zodiac Killer. This cipher was first submitted to the FBI Laboratory on November 13, 1969, but not successfully decrypted. Over the past 51 years CRRU has reviewed numerous proposed solutions from the public–none of which had merit. The cipher was recently solved by a team of three private citizens. The Zodiac Killer case remains an ongoing investigation for the FBI San Francisco division and our local law enforcement partners. The Zodiac Killer terrorized multiple communities across Northern California and even though decades have gone by, we continue to seek justice for the victims of these brutal crimes. Due to the ongoing nature of the investigation, and out of respect for the victims and their families, we will not be providing further comment at this time.''
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/why-the-transposition-in-the-340-solution-is-inevitably-correct/#post-86366 f.reichmann's argument based on unicity distance]
*** [https://zodiackillerfacts.com/news-and-updates/breaking-news-the-zodiacs-340-cipher-has-been-solved/ Full FBI press release was included in Michael Butterfield's article]
* [https://www.youtube.com/watch?v=hIrOftXgibg Nils Kopal's verification]
* [https://eprint.iacr.org/2021/1620 ''Unicity distance of the Zodiac-340 cipher'' by Joachim von zur Gathen]

== More info ==

* [https://www.youtube.com/watch?v=-1oQLPRE21o Solution video 1]
* [https://www.youtube.com/watch?v=UfrFSrI05hk Solution video 2]
* [http://zodiackillerciphers.com/images/z340-key.png Image of the Z340 substitution key]
* [[Compilation of news reports about the solution]]
* [http://www.zodiackillerciphers.com/?p=869 Sam's slides] from his presentation, [https://www.youtube.com/watch?v=iuNyQ44JYxM "The Quest to Solve the Zodiac 340 Cipher"].
* [[Transposition matrices]]

== Timeline of arriving at the solution ==
''Times reported are in Eastern time in the USA''
=== Saturday, January 3, 2015 ===
* 05:56PM: [http://www.zodiackillersite.com/viewtopic.php?p=27087#p27087 Jarl's first post about availability of his new codebreaking software, AZdecrypt. (broken link)] (Jarl told me he had a version of AZdecrypt back in 2014)
** [https://forum.zodiackillerciphers.com/community/zodiac-cipher-mailings-discussion/azdecrypt-beta-0-94/ Working link]

=== Tuesday, July 28, 2015 ===
* 01:02PM: Jarl posts his observations including period 19 bigram repeats [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (original version in Wayback)] [https://zodiackiller.net/community/postid/39170/ (Live version)]
=== Wednesday, August 5, 2015 ===
* 12:45AM: Daikon posts his observations including period 19 bigram repeats [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (original version in Wayback)] [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ Live version]
=== Wednesday, January 16, 2019 ===
* 09:12AM: Sam Blake's first contact with me, via comment on [https://www.youtube.com/watch?v=3Hk__Hk5c9M my 2018 ACA presentation video on Youtube.]
=== Thursday, August 1, 2019 ===
* 09:14PM: Sam Blake starts emailing me enumerations of Z340

=== Sunday, May 17th, 2020 ===
* 07:03AM: Jarl posts a [https://forum.zodiackillerciphers.com/community/zodiac-cipher-mailings-discussion/z340-multiple-transcription-rectangles/ transposition of the 340] which is extremely close to the correct final result.
** [http://zodiackillerciphers.com/jarl-transposition-3-sections-period-19.txt Transcription]
** [http://zodiackillerciphers.com/jarl-transposition-3-sections-period-19-pt.txt Plaintext resulting from applying final Z340 key to his transposed ciphertext]
** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/z340-multiple-transcription-rectangles/ Old broken link]

=== Wednesday, December 2nd, 2020 ===
* 04:14PM: Began running 655,088 ciphers, the cumulative collection of all cipher enumerations and decimations Sam Blake has sent me to date, through AZDecrypt v1.19 with default settings (except for loading jarlve's reddit 6-grams). Had run many of them before, but this time I wanted to be more careful about sorting the results based on the cipher lengths (some manipulations remove parts of the cipher, which sometimes leads to azdecrypt reporting higher scores compared to ones for ciphers of length 340).
=== Thursday, December 3rd, 2020 ===
* 12:04PM: Reported an interesting result to Sam from one of his older vertical 3-split decimations
** [http://www.zodiackillerciphers.com/z340_vertical_3split_decimations_9_9_1_19_2.txt Transcription: z340_vertical_3split_decimations_9_9_1_19_2.txt]
*** [http://www.zodiackillerciphers.com/z340_vertical_3split_decimations_9_9_1_19_2_pt.txt Plaintext resulting from applying the final Z340 key to his transposed ciphertext]
** AZdecrypt generated this candidate plaintext:
*** EHOPE YOU ARE HE SING IST TORRA ENN
*** TRYING TO CATCH METH AFTAINT MT ON THE
*** TS SHOT WHICH BRINGS UP ALS IN TABS IT
*** ME NAME OF AR HEED OR THE GAS CHAMBER
*** BECA ATE IT WILD VENT ME ROLER A DICE
*** AI I THE VS SHEN BECAUSE TOO WHA SEEN
*** TIGHT DESERTS WORS ROS ME THERE
*** EVERYONEED HE HAS NOTHING THEN THEY HE
*** ACH PARADICT IS THEY ALREARE AND NORDER
*** THER AMEO EARRE AND BECAUITE IS YOT TV
*** HAT MR NEWE ITLE NEVER IND BAEYN NEIA
*** AT A HOE CDR PET
** A few interesting legible phrases stood out right away:
*** HOPE YOU ARE
*** TRYING TO CATCH ME
*** SHOT WHICH BRINGS UP
*** OR THE GAS CHAMBER
*** HE HAS NOTHING THEN THEY
** Phrases were more noticeable due to the auto-whitespace feature Jarl added for v1.19.
* 03:25PM: Determined the transposition (decimation) steps that were performed for that cipher among Sam's batch.
* 07:50PM: Sam provides details on the 9,9,1,19,2 enumeration, which is actually split into 4 vertical groups of size 9, 9, 1, and 1. A decimation of 19,2 is applied to each group.
* 09:36PM: I reported to Sam my solution to the first 9 lines, obtained by isolating those 9 lines, feeding them into AZdecrypt, but locking in cribs for some of the interesting phrases discovered earlier.
** The plaintext read: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO CATCH ME THAT WASNT ME ON THE TV SHOW WHICH BRING OR PA POINT ABOUT ME I UM NOT A FRA IF OF THE GAS CHAMBER BECUASE IT WILL SEND ME TO PAY UNLCE ALL THE
** The first section contains every symbol used in the entire cipher, so applying the key to the entire cipher text gave this plaintext: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO CATCH ME THAT WASNT ME ON THE TV SHOW WHICH BRING OR PA POINT ABOUT ME I UM NOT AFRAID OF THE GAS CHAMBER BECUASE IT WILL SEND ME TO PAY UNLCE ALL THE SOO HEN BE CURSEE OOW HAVE ENSUGH SLAVER TO WOR V FOV ME WHERE ESERYONE EL HEH US NOTHING WHEN THEY REACH PAY UNICE SO TREY ALREU FAA I FI OF NET TH IF AM NO EA FREA IF BNC ARISE IV YO WT SHAT MR NEW EIW LENESE FLIL BAAYNNE I UADAHO I CFR PET
** Appearance of phrase "THAT WASNT ME ON THE TV SHOW" locked this in as a solid lead towards a real solution. Second 9 lines yielded from the same key have a relatively high score (compared to random plaintext or gibberish) but is somewhat garbled. Also noticed the word DEATH appearing at the very end of the last line of the entire cipher, using same key as the one discovered for the first 9 lines. Asked Sam for help to figure out the remaining 11 lines.
* 10:04PM: Notified Jarl to also ask for his help.

=== Friday, December 4rd, 2020 ===
* 08:04AM: Ran several other decimations from Sam to try to isolate other schemes that might lead to a solve for the remaining 11 lines.
* 09:29AM: Completed a search of over 400,000 AZdecrypt results and determined that the phrase GAS CHAMBER appears in no other result.
* 10:10AM: Ran some more decimations from Sam. Didn't notice anything substantial in the results.
* 11:19AM: First response from Jarl, "It looks genuine!"
* 02:17PM: I report reversed words in the last 2 lines to Sam and Jarl
* 02:23PM: Jarl independently reports reversed words in the last 2 lines.
* 02:31PM: I interpreted the garbled 2nd section to read like this:
** BECAUSE ? SLAVES TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF LETTING ?? BECAUSE I (VOW?)...
* 02:40PM: Refined 2nd section:
** BECAUSE ??? HAVE ENOUGH SLAVES TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF LETTING ?? BECAUSE I (VOW?)...
* 02:58PM: Jarl reports his refined solution:
**I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING
**TO CATCH ME THAT WASNT ME ON THE TV SHOW
**WHICH BRINGS UP A POINT ABOUT ME I AM NOT
**AFRAID OF THE GAS CHAMBER BECAUSE IT WILL
**SEND ME TO PARADICE ALL THE
**
**SOO HEN BECAUSE EOOW HAVE ENOUGH SLAVES TO
**WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
**WHEN THEY REACH PARADICE SO THEY ALRE UFA AID
**I OF DET TH IF AM NO EA FREA ID BN CA AISE IV
**YO WT SHAT MR NEW
**
**EFIL WILL EB NA EASY E
**NONI ECIDARAP DEATH
* 03:18PM: I report my finding about the errors on line 15 (the 6th line of the 2nd section). Several errors are happening on the same line, suggestive of a systematic mistake.
* 03:23PM: Jarl reports his interpretation of the plaintext:
** SO THEY'RE ALL AFRAID OF DEATH I AM NOT AFRAID BECAUSE IT ...
* 04:19PM: I'm considering sending our partial solve to the FBI so they can help us work out the rest of it
* 05:47PM: Decided against reporting the solve early, to give our team more time to work it out. Developed a visualization of the errors on line 15 (6th line of the 2nd section).

=== Saturday, December 5th, 2020 ===
* 01:26AM: Jarl reports progress on the plaintext, resulting from a possible "skip" in the 2nd part. Jarl's latest plaintext:
** I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING
** TO CATCH ME THAT WASNT ME ON THE TV SHOW
** WHICH BRINGS UP A POINT ABOUT ME I AM NOT
** AFRAID OF THE GAS CHAMBER BECAUSE IT WILL
** SEND ME TO PARADICE (ALL THE)
**
** (SOO HEN) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO (THEYRE ALL) AFRAID
** OF DEATH I AM NOT AFRAID BECAUSE IT
** (YO WT SHAT MR NEW)
**
** EFIL WILL EB NA EASY ENO
** NI ECIDARAP DEATH
* 02:16AM: Jarl reports more detail on the skip in the 15th row, and the skip seems isolated to that row. But still some garble happening after that is fixed.
* 02:41AM: Jarl reports discovery that skipping cleartext "LIFEIS" in upper right section of the 2nd block fixes the remaining garbles. Plaintext now only has a few errors remaining.
* 02:50AM: Jarl reports full plaintext:
** I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING
** TO CATCH ME THAT WASNT ME ON THE TV SHOW
** WHICH BRINGS UP A POINT ABOUT ME I AM NOT
** AFRAID OF THE GAS CHAMBER BECAUSE IT WILL
** SEND ME TO PARADICE (ALL THE)
**
** (SOO HER) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO THEY ARE AFRAID
** OF DEATH I AM NOT AFRAID BECAUSE I KNOW THAT
** MY NEW LIFE IS
**
** EFIL WILL EB NA EASY ENO
** NI ECIDARAP DEATH
* 03:44AM: Jarl reports details on steps that were required to fix the 2nd section:
** Right-offset the RATENYRNOSRVSH fragment by 1 becoming HRATENYRNOSRVS. I think he skipped the H by mistake (during homophonic step) and then realized his error going into the 7th row and added the H back in at the end of the 6th row.
** Skip the positions of the "LIFEIS" fragment during untransposition.
** Now after transposition it will result in:
**
** (SOO HER) BECUASE E NOW HAVE ENOUGH SLAVES TO
** WORV FOR ME WHERE EVERYONE ELSE HUS NOTHING
** WHEN THEY REACH PARUDICE SO THEY ARE UFRAID OF
** DEATH I AM NOT AFRAID BECAASE I VNOW THAT MY NEW
**
** Fixing a few errors:
**
** (SOO HER) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
** DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
**
** Since the "LIFEIS" fragment was skipped it can be added in somewhere else, and I think it has to be at the end:
**
** (SOO HER) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
** DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW (LIFE IS)
* 07:56AM: I completed a PDF report of our solution and submitted it to my contacts at the FBI crypto lab.
* 08:02AM: First response from FBI crypto lab, unofficial confirmation
* 08:48AM: Second response, unofficial confirmation
* 08:49AM: Third response, further confirmation, phone call
Not sure about further timing on this day, but during the day the FBI took action on the solution, notifying others in the agency as well as working on a report of the solution to submit back to SFPD, the original requestor. Submission also planned to SF FBI.
=== Sunday, December 6th, 2020 ===
CRRU submitted the solution to FBI San Francisco in the evening.
Waiting for contact with FBI National Press Office to coordinate release of this news.

=== Monday, December 7th, 2020 ===
Talked to FBI National Press Office in the afternoon to discuss release plan. Allowing for all victim notifications to take place prior to releasing the news.
=== Thursday, December 10th 2020 ===
Talked to FBI National Press Office in the afternoon and was informed that final notifications will be completed by the end of the day and that the best time for the news release will be Friday.

[https://www.tapatalk.com/groups/zodiackillerfr/viewtopic.php?p=159817#p159817 Teased the pending release of the news.]

=== Friday, December 11th 2020 ===
* 06:00AM: [https://youtu.be/-1oQLPRE21o Explainer video (Let's Crack Zodiac Episode 5)] switched to Public. I posted the news on many social media outlets and forums, and emailed the LCZ mailing list.
** Post on [https://www.tapatalk.com/groups/zodiackillerfr/the-340-cipher-has-been-solved-t9434.html#p159875 Tom Voigt's forum]
** Post on [https://forum.zodiackillerciphers.com/community/news-wire/z340-has-been-solved/ Mike Morford's forum]
* 01:03PM: First news report by SF Chronicle, [https://twitter.com/KevinChron/status/1337458070570508289 announced by long time Zodiac reporter Kevin Fagan]
* 02:21PM: FBI San Francisco makes a public announcement of the solution [https://twitter.com/FBISanFrancisco/status/1337477701825925120 on their twitter account.]

Over the next several days, many news outlets reported on the solution.
[http://zodiackillerciphers.com/wiki/index.php?title=Compilation_of_news_reports_about_the_solution Click here for a compilation.]

Crimo Cipher

2025-09-25T11:18:43Z

Admin: /* Other Links */

= Background =

Case information: https://en.wikipedia.org/wiki/Highland_Park_parade_shooting

Robert Eugene Crimo III perpetrated a mass shooting event on July 4th, 2022 in Highland Park, Illinois. He is an aspiring rapper, calling himself "Awake the Rapper", who posted music videos and violent content on social media.

He allegedly published an encrypted manifesto on Amazon. According to [https://web.archive.org/web/20220704225846/https://awake-the-rapper.fandom.com/wiki/Arcturus this Fandom page (formerly Wikia)]:

"''Arcturus, or more formally known as 'Project Arcturus' is an archaic manifesto/book conceived by Robert Crimo (Awake). It was published on the 19th of February in the year 2021. It is 28 pages long and is composed entirely of an undeciphered sequence of numbers. There is a coinciding video to Arcturus on YouTube, which is composed of footage from the music videos to On My Mind, out.of.this.world, and Toy Soldier. The numbers 23, 47, and 115 seem to be of significance in decoding Arcturus, however, Arcturus remains an unsolved mystery.''" [http://zodiackillerciphers.com/images/fandom-arcturus.png (Image)]

Some people reported that the [http://zodiackillerciphers.com/images/crimo-arcturus-amazon-description-morse.png book's description on Amazon contained Morse code translating to "Hello Friend"], which was the name of one of his music videos. In the video, a small building is shown while the camera pans slowly back while haunting music is played. Crimo's [http://zodiackillerciphers.com/images/awaken-rapper-symbol.jpg symbol] appears to be mounted at the top right corner of the building. The scene then switches to a car with the number "47" painted on its side and a red zig zag pattern painted on the front. The haunting music is from the game ''Call of Duty Black Ops Cold War'', a piece titled ''Comrade'' by Jack Wall. [https://www.youtube.com/watch?v=rotQXwQNUo0 (2:08 in this video)]

One of Crimo's videos, titled ''Building A F$@_ing Cabin In The CITY'', shows [http://zodiackillerciphers.com/images/crimo-cabin-feb-2021-date.png the date Feb 2021 printed on an unfinished wall of the cabin]. The same cabin appears in his ''Hello Friend'' video. The manifesto was also apparently published on Feb 2021.

= Connections / Similarities =

=== Alessa tumblr ===

Some people found [https://web.archive.org/web/20220705010713/https://alessa-ormora.tumblr.com/ this tumblr page] which features Awake's symbol in the profile picture. The post contains a mysterious message and a series of symbols (moons, stars, etc.) that resembles an encoded message. [https://alessa-ormora.tumblr.com/ The current version of the page] shows that the profile picture has changed. The archive shows references to Awake the Rapper. It's unclear if the references were made before or after Crimo was arrested.
* [http://zodiackillerciphers.com/images/crimo-music-video-symbols-moon-stars.jpg Moons and stars appearing in one of Crimo's videos]

=== Arcturus Project ===

[http://necrobones.com/seti/arcturus/ The Arcturus project], a seemingly unrelated site, describes a radio signal received from the star ''Arcturus'' in 1997. The signal is described as a binary sequence, and the site appeals to readers to help decode the mysterious signal. However, the task is a fiction constructed to challenge people to complete the decryption, which is a [http://necrobones.com/seti/arcturus/arcturus-messages.gif binary representation of an image containing a further message.]

=== The Arcturus Code ===

A book titled [https://www.amazon.com/gp/product/B09PDND29Z/ref=dbs_a_def_rwt_hsch_vapi_tkin_p1_i0 The Arcturus Code], by Randy Kovicak, is a story about a boy who discovers a mysterious code beaming from the star Arcturus.

=== Equestria At War: Arcturus cipher ===

In a game called [https://equestria-at-war.fandom.com/wiki/Equestria_at_War_Wiki Equestria at War], an "Arcturus Cipher" appears. Evidently it is an ASCII Shift Cipher +41.
* [https://www.reddit.com/r/equestriaatwar/comments/bk2zar/solving_the_arcturus_cipher/ Reddit post 1]
* [https://www.reddit.com/r/equestriaatwar/comments/ddw322/figured_this_wasnt_too_big_of_a_secret_so_i/ Reddit post 2]

= Online discussions =

* Reddit:
** https://www.reddit.com/r/Decoders/comments/vrkmgj/highland_park_illinois_mass_shooter_manifesto/
** https://www.reddit.com/r/codes/comments/vru8o5/highland_park_shooters_video_hidden_messages_in/
** https://www.reddit.com/r/masskillers/comments/vtxrpo/the_two_puzzles_that_were_released_on_amazon/
** https://www.reddit.com/r/masskillers/comments/vttgbu/looking_for_anyone_who_obtained_a_copy_of/
** https://www.reddit.com/r/arcturusdecoded/
** https://www.reddit.com/r/conspiracy/comments/vtp22v/why_isnt_the_highland_park_shooter_suspects/
** https://www.reddit.com/r/masskillers/comments/vrm5fv/this_book_was_written_by_samuel_bromley_a_pen/
** https://www.reddit.com/r/masskillers/comments/vrjwg0/the_july_4_shooters_book_that_he_allegedly_wrote/
* 4chan:
** https://boards.4chan.org/pol/thread/385746537#q385746537
** https://boards.4chan.org/pol/thread/385764770#q385764770
** https://boards.4chan.org/pol/thread/385715785#q385715785
** https://boards.4chan.org/pol/thread/385585797
** https://boards.4chan.org/pol/thread/385602240
* Discord
** [https://discord.com/invite/KRxZkejyWS Overt Operator Discord]
*** Channel: ''#Robert Crimo III - Highland Park Shooting - Arcturus''
*** [https://discordleaks.unicornriot.ninja/discord/user/2337 Archive of Discord posts allegedly made by Crimo]
* Blogs
** [https://scienceblogs.de/klausis-krypto-kolumne/2022/07/15/die-verschluesselte-nachricht-des-highland-park-amoklaeufers/ Cipherbrain post]

= Images =

* [https://imgur.com/a/Yy4OwDZ Images of entire book]
* PDF format:
** [http://zodiackillerciphers.com/robert%20crimo%20-%20arcturus%20encrypted%20book.pdf Version 1]
** [http://www.zodiackillerciphers.com/crimo-rm79q7.pdf Version 2]
** [http://zodiackillerciphers.com/crimo-arcturus-pdf-searchable-version.pdf Version 3] (a searchable transcription converted to PDF format)
* Word search book that was listed on Amazon by the same seller as the Arcturus book. There is speculation it could be a possible key. The book's author is listed as ''Samuel Bromley''.
** [http://www.zodiackillerciphers.com/crimo-kxyd6w.pdf PDF format]

= Transcriptions =

* [http://zodiackillerciphers.com/crimo-preview-transcription.txt Preview page that was posted on reddit]
* [http://zodiackillerciphers.com/Arcturus%20-%20Transcribed/ Full book transcription]
* https://pastebin.com/3L9hPdqP
* http://www.zodiackillerciphers.com/arcturus-transcription-from-discord-johnp.txt

= Observations =

* The book contains 27 pages of numbers.
* Only the first 9 pages are unique. The next 9 and last 9 pages are repeats of the first 9 pages.
* Each page has 38 rows, and 86 characters per row, for a total of 3268 characters per page.
* In some of his online posts, Crimo emphasizes the number 333. The book is 27 pages long which is a perfect cube: 3x3x3.
* Each 9 page group has a total of 29412 characters (88236 for all 27 pages).
* The book's description on Amazon included the phrase "Hello Friend" encoded in Morse code. [http://zodiackillerciphers.com/images/crimo-arcturus-amazon-description-morse.png (Image)]
* One additional book was listed under the same seller on Amazon. The title was ''Classic Large Print Word Search Book For Adults'' [http://zodiackillerciphers.com/images/arcturus-classic-word-search-puzzles.png (Image)]. Being listed together with Arcturus led to speculation it may be a hint or key. PDF of the book is linked above.
** The puzzles vary in size, such as 16x16, 18x18, and 23x23.
* [https://www.evernote.com/l/AAFjslaoBIJEF73cyw1lZQQKB180YbPSKvc JFGariepy's "exhaustive offset analysis"]

= Unigrams =

* [https://en.wikipedia.org/wiki/Index_of_coincidence Index of Coincidence]: 0.104
* [https://imgur.com/dyboAkN Frequency count]
** 9, 1, and 2 have relatively low frequencies.
** 6, 7, and 3 have relatively high frequencies.
* [http://zodiackillerciphers.com/digit-counts-window-size-1000.html Frequency count, window size 1000] (interactive plot)
* There is a backtick character in the bottom right corner of the 2nd, 11th, and 20th pages of numbers. The affect rows still have a length of 86.
* The cipher seems to have a bias against 9s (i.e., there are far fewer 9s than other digits).
** However, 9s seem to cluster together. The average distance between 9s is [https://docs.google.com/spreadsheets/d/1oXdhxDLg1hyX39nlZQNRAdn_j9AH1ZlUa2ZnAiiwfFs/edit?usp=sharing lower than expected based on shuffle tests.] This contributes to repetitions of sequences such as 9191, 9919, 1919, 1991, etc.
* There is evidence of multiple alphabets but with a wide span.

= Ngrams =

* Crimo emphasizes specific numbers in some of his online posts (such as in his videos depicting gun violence).
** 23
** 47
*** This could represent the date of his murders in reverse (7/4).
*** [https://www.marca.com/en/lifestyle/us-news/2022/07/07/62c61fca22601dd3098b45bd.html Crimo's bizarre fixation with the numbers 4 and 7]
*** [http://zodiackillerciphers.com/images/crimo-acura-47.jpg His Acura car with 47 painted on it] [http://zodiackillerciphers.com/images/robert-crimo-acura-1.jpg (View of license plate)] [http://zodiackillerciphers.com/images/robert-crimo-acura-2.jpg (View of car interior)]
*** [http://zodiackillerciphers.com/images/robert-crimo-face-tattoo.png He had 47 tattooed on his face]
*** [http://zodiackillerciphers.com/images/channel-47-crimo-tv.png A TV depicted in one of his posts is tuned to channel 47]
*** A rapper called Capital Steez frequently references the number 47, and uses it in place of swastikas such as [https://www.youtube.com/watch?v=4e6YKnRc5qs on this album cover].
** 115
*** 115 allegedly is part of Crimo's home address
*** Crimo was a fan of the ''Call of Duty - Black Ops'' video game. In the game, [https://callofduty.fandom.com/wiki/Element_115 Element 115] turns Nazis into zombies.
*** A user online claims: ''In one of his videos he has 1+1=5 written on a piece of paper.''
*** [https://web.archive.org/web/20210325054415/https://twitter.com/robertcrimo/status/1374960222641352707 Archive of his Twitter post containing 115 and other numbers]
** 159
*** [https://web.archive.org/web/20220705031726/https://awake-the-rapper.fandom.com/wiki/XADA_159 XADA_159], evidently what Awake named his record label.
** 333
** The numbers 23, 47, and 115 add up to 185. July 4th, the day of the shooting, was the 185th day of the year 2022.
** One person suggested Crimo's [http://zodiackillerciphers.com/images/awaken-rapper-symbol.jpg symbol] can be interpreted as a combination of copies of the number 4.
* [https://imgur.com/OYP28Ak Bigram frequencies]
** 76 is the most common. 23 and 47 are the 13th and 14th most common, respectively
** 94 and 95 have the same frequencies (134).
** 05 and 06 have the same frequencies (166).
* [http://zodiackillerciphers.com/crim-cipher-trigram-counts.txt Trigram frequencies]
* The cipher has high ngram repeats for n=3 through n=7 when compared to random shuffles.
* The number of ngram repeats for n=2 is indistinguishable from the quantity expected during random shuffles, but [https://docs.google.com/spreadsheets/d/1WU3GJiPYINFiw8gVVSfFtCinZP7sAcOWTeS6OluLW2k/edit?usp=sharing n-graphic IoC tests suggest the specific repetitions are significant]
* The cipher has a very strong bias towards sequences of successive digits (01, 10, 23, 34, 45, 98, 87, etc).
** Going from 23 to 34 to 45, for example, can be done by adding 11 to each number. Crimo emphasizes the number 47 in his posts and tattoos, and 4+7=11.
* The cipher has a strong bias against sequences of doubles (22, 33, 44, etc).
** This does not apply to the doubles 00, 66 and 99.
* Numbers 1 and 2 are more likely to be found before or after the number 0.
* Number 9 is more likely to be preceded or followed by 1 and 2.
* Number 7 is more likely to be before or after a 6.
** Number 7 is also more likely to be 2 positions away from a number 6 in both directions.
* [https://docs.google.com/spreadsheets/d/1g9PjRvCofS2q-ug6VM8eQplTdedN4HkALLqTXuL_Yyc/edit?usp=sharing Digit sequence counts compared to expected]
* [https://www.evernote.com/l/AAEaZHs2In5MKZJ4cno3knK6c3gisdxBFUY JFGariepy observations from Discord]
=== Heat Maps ===
* [http://zodiackillerciphers.com/images/crimo-cipher-bigram-heatmap.png Bigram 2D heatmap]
* [http://zodiackillerciphers.com/crimo-cipher-heatmap-3d/index.html Bigram 3D heatmap] (Interactive. Zoom, rotate, and pan with your mouse.)
* [http://zodiackillerciphers.com/crimo-cipher-heatmap-3d/scatter3d.html Trigram 3D heatmap] (Interactive. Zoom, rotate, and pan with your mouse.)

= Cycles =

* The cipher appears to demonstrate some cycling behavior.

= Sliding Window tests =

Does the cipher have consistent statistics throughout? If not, maybe that is evidence of a different scheme being used in different sections. The following plots use a window size of 1000 applied to different parts of the first 9 pages of Crimo's cipher. The plots marked "no overlap" move the window 1000 positions forward with each step. The ones marked "overlap" move the window 1 position with each step.

=== Index of Coincidence ===

* Unigrams
** [http://zodiackillerciphers.com/images/sliding-windows/ioc-no-overlap.png IoC (no overlap)]
** [http://zodiackillerciphers.com/images/sliding-windows/ioc-overlap.png IoC (overlap)]
* Bigrams
** [http://zodiackillerciphers.com/images/sliding-windows/digraphic-ioc-no-overlap.png Digraphic IoC (no overlap)]
** [http://zodiackillerciphers.com/images/sliding-windows/digraphic-ioc-overlap.png Digraphic IoC (overlap)]

=== Homophone cycles (length 2) ===

* [http://zodiackillerciphers.com/images/sliding-windows/2cycles-no-overlap.png Composite cycle score (no overlap)]
* [http://zodiackillerciphers.com/images/sliding-windows/2cycles-overlap.png Composite cycle score (overlap)]

=== Keyboard number distance tests ===

* 1D layout
** [http://zodiackillerciphers.com/images/sliding-windows/and-1d-no-overlap.png Average number distance (no overlap)]
** [http://zodiackillerciphers.com/images/sliding-windows/and-1d-overlap.png Average number distance (overlap)]
* 2D layout
** [http://zodiackillerciphers.com/images/sliding-windows/and-2d-no-overlap.png Average number distance (no overlap)]
** [http://zodiackillerciphers.com/images/sliding-windows/and-2d-overlap.png Average number distance (overlap)]

= Keyboard test =

Did Crimo simply "mash the keyboard" to generate a seemingly random sequence of digits?
What if the distance between successive number reflects short distances between number keys on his keyboard?
I made three measurements:

* Average distance between successive digits, based on 1D layout of number keys (horizontal row on standard keyboard).
** Observed to be 29 sigma above average compared to shuffles.
* Average distance between successive digits, based on 2D layout of number keys on a standard number pad on extended keyboards.
** Observed to be 13 sigma above average compared to shuffles.
* Average distance between successive digits, based on simple absolute difference of the digits.
** Observed to be 6 sigma below average compared to shuffles.

[http://zodiackillerciphers.com/images/keyboard-number-distance-shuffle-tests-results.png Table of shuffle test results]

= Ideas for experiments to perform / TODO =

* Pollux was ruled out. But what if he used a custom Morse alphabet?
** Experiment: Ignore the standard Morse alphabet. Determine all dot/dash/space mappings that produce:
*** A sequence consisting of no more than ~26 distinct Morse-like patterns (units).
*** With valid use of spaces in between the patterns (i.e., only one or two spaces should appear between Morse units)
** There are differences between [https://www.britannica.com/topic/International-Morse-Code American and International Morse.]
** Test for larger Morse-like alphabets (for example: dot, dash, star, moon; resembling [https://web.archive.org/web/20220705010713/https://alessa-ormora.tumblr.com/ this cipher-like message]). Determine assignments of sets of digits that partition groups of ''n'' custom symbols into an alphabet-sized set.
* What if he used Pollux but didn't use spaces? The Morse sequence would have many ambiguous interpretations.
** Experiment: Polyalphabetic Pollux? I.e., symbol groups may have overlapping assignments: Dash: 0 1 4 3 6, Dot: 3 8 7 4, Space: 4 5 2 9 6.
* Run similar experiments to rule out Morbit.
* Make heatmaps of ngram frequencies
* Crimo was heavily influenced by the ''Call of Duty'' video game. Are there any ciphers in the game? Could he have been influenced by them?
** [https://scienceblogs.de/klausis-krypto-kolumne/2020/09/06/who-can-break-this-cryptogram-from-the-computer-game-call-of-duties/ Article describing various ''Call of Duty'' ciphers]
* In [https://twitter.com/krimp233/status/1544122489839751168 this video] Crimo appears to be watching a video of the ''Gravity Falls'' theme song. ''Gravity Falls'' is a show that [https://screenrant.com/gravity-falls-cryptogram-ciphers-solve/amp/ features ciphers.] Look for any relevant encipherment schemes.
* Do a more detailed periodic ngram analysis.
* Try to obtain the document that was originally [https://web.archive.org/web/20210325054410/https://www.awake.rip/ linked here], titled ''Awake Short Auto-Biography Paper''.
* Calculate average difference between successive numbers
** Compare to "keyboard distance"
** Compare to number keypad distances
** Test for hand dominance (i.e., each half of a row of number keys might cluster together in the cipher)
* Calculate compression rate compared to random shuffles, as a way to estimate non-randomness in the cipher.
* Calculate symmetry of ngram counts (for example, the pairs of bigrams {01,10}, and {67,76} have roughly similar counts).
* Test for longer repeating ngram patterns allowing for a fixed number of permitted errors / skips / nulls.

= Other Links =

* [https://antonhoyer.com/arcturus Arctus: Not a Cipher], analysis by Anton Hoyer
* [https://web.archive.org/web/20220201132352/https://youtube.fandom.com/wiki/Awake Youtube fandom entry for Awake (archived)]
* [https://www.evernote.com/l/AAH2SYvQdyBBI7VkRUoMVVd97EWWmlgLLUI Awake Fandom (Wikia) entries from Google Cache and Wayback]
* Awake official sites:
** [https://web.archive.org/web/*/awake.rip Site 1 (Archived)]
** [https://web.archive.org/web/*/https://www.awaketherapper.com/ Site 2 (Archived)]
* [https://web.archive.org/web/20220704222318/twitter.com/homeisgone Possible Awake the Rapper twitter account (Archived)]
* [https://gist.github.com/travisbrown/5806909a61ca815191f823d39d5137e7 Collection of archived tweets]

Halloween card

2025-09-03T19:07:16Z

Admin: /* Animals */

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Astronomy ===

* [https://imgur.com/a/gNWSz4t Constellation Cassiopeia]

=== Animals ===

* [http://zodiackillerciphers.com/images/viera-horse-farm.png Viera Horse Farm] [https://discord.com/channels/1260505612131897375/1371524514558509146/1372751043678441512 (source)]

==== Cattle Brands ====

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

==== Bird / Bat ====

The "Claude" AI gave this interpretation of the image: "This symbol appears to be a simple line drawing resembling a stylized bird or bat shape, with two angled lines forming what could be interpreted as wings, and two dots suggesting eyes."

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."
* [https://forum.zodiackillerciphers.com/community/postid/79587/ A reference to Z340's transposition scheme]

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Gang Symbology ===

* Hell's Angels (unconfirmed / possibly faked)
** [https://www.reddit.com/r/ZodiacKiller/comments/1inpo6c/hells_angels_mc/ Reddit link]
** [https://x.com/candymugs/status/1889068385352233179 @candymugs post 1]
** [https://x.com/candymugs/status/1889122490003140678 @candymugs post 2]
** [https://x.com/candymugs/status/1889457601131266234 @candymugs post 3 (video clip)]
** [https://x.com/candymugs/status/1889472683345166368 @candymugs post 4]

=== Graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Military ===

* Kevin Robert Brooks, whose suspect is Donald Bujok, said VF4 (or just 4F) is a military classification for mentally unfit. [https://discord.com/channels/996952324150931477/996952376894292018/1322755033179357224 (source)]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]
* [https://en.wikipedia.org/wiki/Alchemical_symbol Alchemical symbols]
** Specifically, [https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Aqua_fortis.svg/48px-Aqua_fortis.svg.png the symbol for "Aqua fortis"]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
** [https://discord.com/channels/1260505612131897375/1268237379299315742/1374485197139218663 (Discord)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]
* [https://www.tapatalk.com/groups/zodiackillerfr/wide-flange-beam-gaik-t2170.html "GAIK" in Brahmi alphabet]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Halloween card

2025-09-03T16:47:59Z

Admin: /* Writing systems / early alphabets */

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Animals ===

* [http://zodiackillerciphers.com/images/viera-horse-farm.png Viera Horse Farm] [https://discord.com/channels/1260505612131897375/1371524514558509146/1372751043678441512 (source)]

==== Cattle Brands ====

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

==== Bird / Bat ====

The "Claude" AI gave this interpretation of the image: "This symbol appears to be a simple line drawing resembling a stylized bird or bat shape, with two angled lines forming what could be interpreted as wings, and two dots suggesting eyes."

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."
* [https://forum.zodiackillerciphers.com/community/postid/79587/ A reference to Z340's transposition scheme]

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Gang Symbology ===

* Hell's Angels (unconfirmed / possibly faked)
** [https://www.reddit.com/r/ZodiacKiller/comments/1inpo6c/hells_angels_mc/ Reddit link]
** [https://x.com/candymugs/status/1889068385352233179 @candymugs post 1]
** [https://x.com/candymugs/status/1889122490003140678 @candymugs post 2]
** [https://x.com/candymugs/status/1889457601131266234 @candymugs post 3 (video clip)]
** [https://x.com/candymugs/status/1889472683345166368 @candymugs post 4]

=== Graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Military ===

* Kevin Robert Brooks, whose suspect is Donald Bujok, said VF4 (or just 4F) is a military classification for mentally unfit. [https://discord.com/channels/996952324150931477/996952376894292018/1322755033179357224 (source)]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]
* [https://en.wikipedia.org/wiki/Alchemical_symbol Alchemical symbols]
** Specifically, [https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Aqua_fortis.svg/48px-Aqua_fortis.svg.png the symbol for "Aqua fortis"]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
** [https://discord.com/channels/1260505612131897375/1268237379299315742/1374485197139218663 (Discord)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]
* [https://www.tapatalk.com/groups/zodiackillerfr/wide-flange-beam-gaik-t2170.html "GAIK" in Brahmi alphabet]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Halloween card

2025-08-16T19:58:31Z

Admin: /* Animals */

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Animals ===

* [http://zodiackillerciphers.com/images/viera-horse-farm.png Viera Horse Farm] [https://discord.com/channels/1260505612131897375/1371524514558509146/1372751043678441512 (source)]

==== Cattle Brands ====

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

==== Bird / Bat ====

The "Claude" AI gave this interpretation of the image: "This symbol appears to be a simple line drawing resembling a stylized bird or bat shape, with two angled lines forming what could be interpreted as wings, and two dots suggesting eyes."

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."
* [https://forum.zodiackillerciphers.com/community/postid/79587/ A reference to Z340's transposition scheme]

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Gang Symbology ===

* Hell's Angels (unconfirmed / possibly faked)
** [https://www.reddit.com/r/ZodiacKiller/comments/1inpo6c/hells_angels_mc/ Reddit link]
** [https://x.com/candymugs/status/1889068385352233179 @candymugs post 1]
** [https://x.com/candymugs/status/1889122490003140678 @candymugs post 2]
** [https://x.com/candymugs/status/1889457601131266234 @candymugs post 3 (video clip)]
** [https://x.com/candymugs/status/1889472683345166368 @candymugs post 4]

=== Graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Military ===

* Kevin Robert Brooks, whose suspect is Donald Bujok, said VF4 (or just 4F) is a military classification for mentally unfit. [https://discord.com/channels/996952324150931477/996952376894292018/1322755033179357224 (source)]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]
* [https://en.wikipedia.org/wiki/Alchemical_symbol Alchemical symbols]
** Specifically, [https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Aqua_fortis.svg/48px-Aqua_fortis.svg.png the symbol for "Aqua fortis"]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]
* [https://www.tapatalk.com/groups/zodiackillerfr/wide-flange-beam-gaik-t2170.html "GAIK" in Brahmi alphabet]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Halloween card

2025-08-16T19:58:02Z

Admin: /* Animals */

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Animals ===

* [http://zodiackillerciphers.com/images/viera-horse-farm.png Viera Horse Farm]

==== Cattle Brands ====

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

==== Bird / Bat ====

The "Claude" AI gave this interpretation of the image: "This symbol appears to be a simple line drawing resembling a stylized bird or bat shape, with two angled lines forming what could be interpreted as wings, and two dots suggesting eyes."

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."
* [https://forum.zodiackillerciphers.com/community/postid/79587/ A reference to Z340's transposition scheme]

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Gang Symbology ===

* Hell's Angels (unconfirmed / possibly faked)
** [https://www.reddit.com/r/ZodiacKiller/comments/1inpo6c/hells_angels_mc/ Reddit link]
** [https://x.com/candymugs/status/1889068385352233179 @candymugs post 1]
** [https://x.com/candymugs/status/1889122490003140678 @candymugs post 2]
** [https://x.com/candymugs/status/1889457601131266234 @candymugs post 3 (video clip)]
** [https://x.com/candymugs/status/1889472683345166368 @candymugs post 4]

=== Graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Military ===

* Kevin Robert Brooks, whose suspect is Donald Bujok, said VF4 (or just 4F) is a military classification for mentally unfit. [https://discord.com/channels/996952324150931477/996952376894292018/1322755033179357224 (source)]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]
* [https://en.wikipedia.org/wiki/Alchemical_symbol Alchemical symbols]
** Specifically, [https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Aqua_fortis.svg/48px-Aqua_fortis.svg.png the symbol for "Aqua fortis"]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]
* [https://www.tapatalk.com/groups/zodiackillerfr/wide-flange-beam-gaik-t2170.html "GAIK" in Brahmi alphabet]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Encyclopedia of observations

2025-04-16T16:15:55Z

Admin: /* Observations related to the discovered plaintext and encipherment method */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve])

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]
* Z340's alphabet consists of 63 unique symbols. Coincidentally, the lengths of Z18, Z13, and Z32 add up to 63. (source: @rogerverreault8682 on YouTube)

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.
* 9 out of 14 of the plaintext letters forming the pivots involve the letters A, E, or N. In both the 340 and 408 keys, the backwards L symbol decodes to A, the N symbol decodes to E, and the D symbol decodes to N. Those are the only symbols that decode to the same letter. Also, Z13 begins with the same three letters: AEN. [https://www.reddit.com/r/ZodiacExtortion/comments/1f3hqsl/pivot_patterns_with_aen_symbols/ (Source: Sam Fisher)]

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]
* If you count the letters in "life is" and the shifted letters "ratenyrnosrvs", they add up to 19 (the period required to transpose the plaintext) (Source: @timpsensky5181 on YouTube)

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Z13 Solutions

2025-04-10T10:21:22Z

Admin: /* From "Jasper" */

= Solutions that fit the ciphertext as is =

This section only shows proposed solutions that fit the cipher text "as is". No anagramming or other re-arrangements are used here, and the cipher is considered to be strictly a substitution cipher. Solutions that permit anagramming are very easy to come by, as there are several billion possible string combinations to choose from. Solutions that do not require anagramming are still numerous, however, which increases the difficulty of knowing which one is correct.

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=50&t=1390&p=24191#p24190 "Quill"] ==
* Eddie Penerden
* Stan T E Case (using "8"s as spaces)
* Greg N A Vega (using "8"s as spaces)

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5677 "glurk"] (homophonic solutions) ==
* Steve Pete West
* Adrian a Harrah
* Shannon E Nease
* Steve Pete Best
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Eddie Gene Oden
* Steve Pete Vest
* Barney E Yearby
* Gene Lyle Lange
* Eddie Gene Eden
* Ed Steven Eisen
* E Alva Vanallen
* Angelo Lyle Gay
* Eddie Rene Oden
* Isreal a Sarris
* Carl Bob Abarca
* Elliot O Roller
* Andre Reyes Day
* Ed Steve Nelsen
* Shane Pete East
* Lee Gene Levell
* Eddie Rene Eden
* Rueben E Segers
* Rueben E Severs
* Eddie Gene Aden
* Eddie Dewey Dew
* Shane Pete Mast
* Ed Steve Reeser
* Ed Steve Reiser
* Lee Rene Levell
* Neal Alan Amann
* Sean Lyle Lease
* Otto Alan Alton
* Otto Alan Acton
* Otto Alan Aston
* Otto Alan Anton
* Eddie Rene Aden
* Lee Jamal Abell
* Andre Gene Adan
* Reed Alan Ahern
* Shane Pete Fast
* Elliot O Yokley
* Elliot O Soules
* Lee Pete Levell
* Ira Lamar Adair
* Neil Lyle Laine
* Teodoro Tom Ott
* Otto Adam Altom
* Noah Alan Amann
* Eddy Alan Alden
* Lee Jewel Ezell
* Cory Bob Abarca
* Andre Rene Adan
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Earle Gene Wren
* Dean Rory Ready
* Dana Bob Obando
* Luis Rory Reily
* Otto Asa Santos
* Eric Asa Rapier
* Gino Lyle Lange
* Eddy Alan Arden
* Kent Lyle Linke
* Andre Dewey Daw
* Eddie Les Eades
* Louie Pete Ault
* Eddie Jewel Dew
* Ian Reyes Ennis
* Edison O Rosier
* Ollie Lee Enloe
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Ira Jamar Adair
* Earle Rene Wren
* Ernie Dewey New
* Lee Jewel Ewell
* Eddie Wes Eades
* Drew Rory Reedy
* Al Isaias Arias
* Ollie Derek Lor
* Cary Bob Abarca
* Emile Gene Lien
* Arlie Dewey Law
* Ollie Dewey Low
* Rob Dewey Embry
* Curt Bob Abarca
* Earl Asa Laurel
* Stefan Asa Hess
* Eddie Reyes Dey
* Eli Dana Rapier
* Dane Bob Obando
* Elmo Rory Ramey
* Lee Jere Levell
* Ali Rufus Urias
* Emile Rene Lien
* Eddie Jere Eder
* Stan Lyle Lease
* Chi Derek Edick
* Earle Gene Oren
* Emile Gene Bien
* Earle Gene Uren
* Arturo Rory Tao
* Otis Asa Nation
* Genaro Rory Ngo
* Dane Lyle Linde
* Dane Lyle Lynde
* Dane Lyle Lunde
* Scot Lyle Loose
* Ali Reyes Elias
* Art Solomon Tam
* Donn Bob Obando
* Dino Bob Obando
* Andre Jewel Daw
* Neal Adan Amann
* Emile Rene Bien
* Otto Adan Alton
* Earle Rene Uren
* Otto Adan Acton
* Earle Rene Oren
* Otto Adan Anton
* Otto Adan Aston
* Dallas Asa Olds
* Erik Asa Rapier
* Reed Adan Ahern
* Ernie Jewel New
* Donn Lyle Linde
* Dino Lyle Linde
* Donn Lyle Lynde
* Dino Lyle Lunde
* Donn Lyle Lunde
* Dino Lyle Lynde
* Dong Bob Obando
* Teodoro Tod Ott
* Stefan Asa Bess
* Noah Adan Amann
* Arlie Jewel Law
* Issac Jc Ocasio
* Arlie Reyes Lay
* Ed Teodoro Ater
* Ollie Jewel Low
* Eddy Adan Alden
* Shad Lyle Lease
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Shon Lyle Loose
* Dong Lyle Lunde
* Ollie Reyes Loy
* Stefan Asa Ness
* Earle Dewey Rew
* Reed Asa Sayers
* Anibal Asa Dias
* Noe Reyes Edens
* Delmar Asa Olds
* Isreal Al Abril
* Isreal Al April
* Earle Reyes Rey
* Ernie Les Eanes
* Eddy Adan Arden
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Ernie Reyes Ney
* Morgan Asa Arms
* Olin Asa Nation
* Lou Solomon Ulm
* Ernie Wes Eanes
* Ernie Rey Edney
* Odis Asa Nation
* Murray Asa Arms
* Noe Reyes Evens
* Ollie Dee Enloe
* Leif Rory Reily
* Elmo Asa Raymer
* Isaiah Asa Sais
* Anibal Asa Bias
* Ollie Jere Flor
* Reed Asa Sagers
* Reed Asa Sauers
* Stefan Asa Vess
* Stefan Asa Jess
* Stefan Asa Gess
* Ezra Asa Laurel
* Erin Asa Rapier
* Emile Jere Mier
* Emile Jere Pier
* Emile Jere Bier
* Earle Jewel Rew
* Emile Jere Wier
* Emile Jere Kier
* Anibal Asa Sias
* Isaias Asa Sais
* Paris Asa Serpa
* Arlie Jere Klar
* Luigi Gil Ifill
* Hai Solomon Ihm
* Darell L Ilardi
* Chi Derek Emick
* Eddie Lee Emdee
* Daryl Al Ilardi
* Arlie Rey Emlay
* Eddie Rene Iden
* Chi Derek Enick
* Earle Rene Hren
* Trevor O Howeth
* Earle Gene Hren
* Duncan Asa Ends
* Danial Asa Ends
* Louie Pete Hult
* Eddie Gene Iden
* Chas Asa Kasack
* Clay Asa Kasack
* Lee Jewel Euell
* Chad Asa Kasack
* Ian Dana Katnik
* Chet Asa Kazeck
* Shane Pete Kast
* Leo Jewel Etoll
* Ian Dana Kamnik
* M Keenan Ingemi
* M Vernon Ingemi
* Ernie Jere Iner
* Eddie Dee Emdee
* Isaias Asa Kais
* Ed Steven Elsen
* Steve Pete Jest
* Isaiah Asa Kais
* Theron O Howeth
* Neil Asa Garing
* Ernie Wes Ennes
* Noah Asa Galang
* Shane Leo Eraso
* Steve Pete Gest
* Emile Jere Gier
* Israel E Gehrig
* N Eugene Genung
* Neal Asa Galang
* Elijah Asa Fies
* Steve Pete Fest
* Eli Peter Etier
* Ed Steven Essen
* Stefan Asa Fess
* Chi Derek Erick
* Ollie Pete Flot
* Earle Pete Fret
* Ernie Ben Ennen
* Emile Jere Hier
* Ernie Len Ennen
* Ernie Ken Ennen
* Theron O Horeth
* Trevor O Horeth
* Lee Bo Holowell
* Chi Derek Evick
* Ernie Les Ennes
* Adrian Asa Gras
* Earle Gene Gren
* Noe Reyes Ewens
* Ollie Jere Glor
* Shad Asa Habash
* Stan Asa Habash
* Earle Rene Gren
* Sean Asa Habash
* Aldo Alan Ardan
* Andy Adan Ardan
* Art Jamal Antal
* Aldo Adan Ardan
* Eli Jamal Ariel
* Elijah Al Ariel
* Andy Alan Ardan
* Dorian Asa Ards
* Leland N Analla
* R Keenan Andera
* Lee Jamal Amell
* Ty Isaiah Amith
* L Vernon Angela
* Antwan Al Antal
* R Vernon Andera
* L Keenan Angela
* Ed Isaias Aries
* Art Jamal Attal
* Elmo Adan Aumen
* Shane Peter Ast
* Antwan Al Attal
* Otto Alan Auton
* Isreal Al Avril
* Elmo Alan Aumen
* Otto Adan Auton
* Elmo Alan Armen
* Norman Asa Arns
* Isreal Asa Aris
* Elmo Adan Armen
* Alva Adan Arvan
* Alva Alan Arvan
* Otto Adan Arton
* Otto Alan Arton
* Otto Adan Afton
* Otto Alan Afton
* Eddie Jere Ader
* Duane Reyes Ady
* Isaias Adam Aid
* Isaias Adan Aid
* Isaiah Adam Aid
* Isaiah Adan Aid
* Lyle Bob Abella
* Blake Peter Abt
* Ira Jamar Abair
* Ira Lamar Abair
* Chase Reyes Acy
* Lee Jamal Adell
* Tobias Asa Abts
* Derick C Acorda
* Otto Adan Aiton
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Aron Adan Aloan
* Aron Alan Aloan
* Amos Adan Aloan
* Amos Alan Aloan
* Arlie Gene Alan
* Arlie Rene Alan
* Otto Alan Aiton
* Nigel Al Alagna
* Cecil Al Alecca
* Al Isaias Alias
* Arlie Jere Alar
* Bradly L Aldaba
* Arlie Jewell Aw
* Emile Jere Dier
* Elijah Asa Dies
* Emile Gene Dien
* Emile Rene Dien
* Rey Reyes Eayrs
* Roy Reyes Eayrs
* Les Dewey Easly
* Ray Reyes Eayrs
* Earl E Deserres
* Eddie Derek Der
* Earle Deserres
* Stefan Asa Dess
* Steve Pete Dest
* Ezra E Deserres
* Shelby Bob Deso
* Royce Les Eayrs
* Eddie Ben Elden
* Eddie Ken Elden
* Eddie Ken Eiden
* Eddie Len Eiden
* Chi Derek Elick
* Lee Solomon Elm
* Eddie Len Elden
* Ali Keven Elian
* Lee Jewel Edell
* Arlie Leo Edlao
* Royce Wes Eayrs
* Ed Steven Ebsen
* Al Steven Ehsan
* Eddie Ben Eiden
* Reuben Ed Efurd
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* Earle Rene Bren
* Robert Rory Bro
* L Rocco Cachola
* L Royce Cachola
* Royce Rene Byrn
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Otto Adan Axton
* Otto Alan Axton
* Adrian Asa Bras
* Earle Gene Bren
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Leo Gene Debold
* Leo Jere Debold
* Isaias Asa Dais
* Andre Derek Dar
* Leonel E Debold
* Lionel E Debold
* Leo Pete Debold
* Leo Rene Debold
* N Royce Cicconi
* Arlie Gene Clan
* N Boyce Cicconi
* N Rocco Cicconi
* Bruce Jere Cubr
* Isaiah Asa Dais
* Arlie Rene Clan
* Arlie Jere Clar
* Cleo Asa Kazeck
* Dean Rory Roady
* Ryan Rory Roary
* Ed Luigi Riller
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elwood O Rohwer
* Elmo Rory Romey
* Ed Luigi Rigler
* Deon Rory Rhody
* Dion Rory Rhody
* Eli Rene Revier
* Eliseo E Revier
* Ed Luigi Ridler
* Drew Rory Riedy
* Doug Rory Rhudy
* Anibal Asa Rias
* Dino Rory Rondy
* Ivan Asa Salais
* Silas Asa Salsa
* Isaiah a Salais
* Isaias a Salais
* Thomas a Sanots
* Troy Asa Sanots
* Alva Asa Salvas
* Denis Asa Sanda
* Ira Dana Salais
* Cesar Ira Rosca
* Drew Rory Ruedy
* Dong Rory Rondy
* Donn Rory Rondy
* Neil Asa Sabins
* Eloy Asa Sagoes
* Truman Asa Ruts
* Emery Ty Ryneer
* Eli Gene Regier
* Eli Jere Regier
* Ryan Rory Reary
* Ed Steve Reaser
* Eliseo E Regier
* Elmo Rory Remey
* Eli Pete Regier
* Eli Rene Regier
* Ezra Rory Rarey
* Dana Rory Randy
* Dane Rory Randy
* Art Dana Rajtar
* Elmo Asa Rammer
* Donn Rory Randy
* Earl Rory Rarey
* Dino Rory Randy
* Dong Rory Randy
* Eli Gene Renier
* Eddy E Resendes
* Stefan Asa Ress
* Ed Dee Resendes
* Eli Jere Revier
* Eli Pete Revier
* Alva Rory Revay
* Eli Gene Revier
* Eddie Resendes
* Eli Rene Renier
* Eliseo E Renier
* Eli Jere Renier
* Eli Pete Renier
* Art Pete Rentar
* Art Rene Rentar
* Art Gene Rentar
* Art Jere Rentar
* Alva Asa Sarvas
* Emmitt Ty Tomey
* Emmett Ty Tumey
* Emile Pete Tiet
* Emmett Ty Tomey
* Isaiah Asa Vais
* Isaias Asa Vais
* Emmitt Ty Tumey
* Benito Ty Tunby
* Emile Jere Tier
* T Dusty Tatsuta
* T Rusty Tatsuta
* Noe Dana Talent
* Noel Asa Talent
* Emile Gene Tien
* Emile Rene Tien
* Stefan Asa Tess
* Steve Pete Test
* E Otha Vanasten
* Elijah Asa Wies
* Isaiah Asa Zais
* Emile Gene Wien
* Emile Rene Wien
* Emile Rene Zien
* Emile Jere Zier
* Isaias Asa Zais
* Emile Gene Zien
* Stefan Asa Wess
* Emile Rene Vien
* Emile Jere Vier
* Anibal Asa Vias
* Emile Gene Vien
* N Mike Wedekind
* Neil E Wedekind
* Isaiah Asa Wais
* Isaias Asa Wais
* Ali Gene Setias
* Ali Jere Setias
* Noe Rene Serens
* Moses Asa Sesma
* Louis Asa Shula
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Noe Pete Serens
* Ezra Asa Sayres
* Rueben E Sebers
* Reed Asa Savers
* Earl Asa Sayres
* Noe Gene Serens
* Noe Jere Serens
* Miles Asa Selma
* Myles Asa Selma
* Emile Gene Sien
* Thad Asa Tabatt
* Tuan Asa Tabatt
* Ed Teodoro Ster
* Louie Pete Sult
* Duane Pete Tadt
* Graham Asa Tags
* Leo Dana Tabolt
* Leon Asa Tabolt
* Antwan Asa Stas
* Al Luigi Sillas
* Ed Luigi Sirles
* Emile Rene Sien
* Emile Jere Sier
* Louis Asa Soula
* Al Teodoro Star
* Ollie Pete Slot
* Edison O Solies
* Shelby Bob Leso
* Stefan Asa Less
* Tony Lyle Lente
* Zane Lyle Lenze
* Bret Lyle Liebe
* Elijah Asa Lies
* Anibal Asa Lias
* Robt Lyle Libre
* King Lyle Lenke
* Lee Dana Layell
* Eddy Lyle Ledee
* Arlie Keven Lav
* Lee Dana Lavell
* Lyle Lyle Lelle
* Kent Lyle Lenke
* Theo Lyle Leete
* Trey Lyle Leete
* Gene Lyle Longe
* Gino Lyle Lynge
* Isaiah Asa Mais
* Cecil Eli Lucci
* Gene Lyle Lynge
* I Otha Masaitis
* C Mike Mehelich
* Isaias Asa Mais
* Eddy a Marander
* Cecil Ali Lucci
* Daryl Eli Lordi
* Earl Lyle Loree
* Gino Lyle Longe
* Daryl Ali Lordi
* Ollie Peter Lot
* Paul Lyle Loupe
* Ezra Lyle Loree
* Gary Lyle Lorge
* Alvaro R Krivak
* Cletus U Kubeck
* W Rocky Knknown
* Adrian Asa Kras
* Duane Pete Ladt
* Isaiah Asa Lais
* Robt Lyle Labre
* Lee Dana Ladell
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Keenan Asa Keks
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Stefan Asa Kess
* Isaias Asa Lais
* Kurt Lyle Larke
* Vern Lyle Larve
* Kirk Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Lee Dana Lasell
* Shane Pete Last
* Karl Lyle Larke
* Dane Lyle Lande
* Dino Lyle Lande
* Elmo Asa Lammel
* Dana Lyle Lande
* Zane Lyle Lanze
* Dirk Lyle Larde
* Dong Lyle Lande
* Donn Lyle Lande
* Stefan Asa Mess
* Genaro R Orengo
* Isreal Asa Oris
* Otto Everett or
* Adrian Asa Oras
* Al Teodoro Otar
* Santo Coy Ounsy
* Morgan Asa Orms
* Murray Asa Orms
* Teodoro O Omoto
* Steve Pete Oest
* Emile Gene Oien
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Leo Solomon Olm
* Emile Rene Oien
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raemer
* Eddy Asa Raider
* Eddy Asa Radder
* Eddy Asa Raeder
* Isaias Asa Rais
* Antwan a Rajtar
* Elmo Asa Raimer
* Isaiah Asa Rais
* Adrian Adan Rad
* Isaias Asa Pais
* Elijah Asa Pies
* Ollie Jewell Ow
* Isaiah Asa Pais
* Rupert Rory Pro
* Adrian Adam Rad
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Isaias a Narain
* Ivan Asa Narain
* Steve Pete Nest
* Ernie Peter Net
* Ed Steve Neisen
* Ed Steve Nessen
* Isaiah a Narain
* Shannon Z Naasz
* Odis Asa Nacion
* Anibal Asa Mias
* Al Luigi Millam
* Otto Asa Nanton
* Ira Dana Narain
* Olin Asa Nacion
* Otis Asa Nacion
* Ernie Keven Nev
* L Damon Odonald
* L Daron Odonald
* L Aaron Odonald
* L Carol Odonald
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* L Jarod Odonald
* Eddie Jere Oder
* Austin I Nissan
* Elliot O Nowlen
* Emile Jere Nier
* Ian Solomon Nim
* Neal Bob Obiano
* Noah Bob Obiano
* Elroy Ty Nygren
* Emery Ty Nyreen
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5733 "glurk"] (non-homophonic solutions) ==
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Angelo Lyle Gay
* Andre Reyes Day
* Shane Pete Mast
* Shane Pete Fast
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Dean Rory Ready
* Luis Rory Reily
* Gino Lyle Lange
* Louie Pete Ault
* Edison O Rosier
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Arlie Dewey Law
* Rob Dewey Embry
* Eli Dana Rapier
* Elmo Rory Ramey
* Ali Rufus Urias
* Chi Derek Edick
* Otis Asa Nation
* Ali Reyes Elias
* Art Solomon Tam
* Andre Jewel Daw
* Dino Lyle Linde
* Dino Lyle Lunde
* Dino Lyle Lynde
* Arlie Reyes Lay
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Dong Lyle Lunde
* Delmar Asa Olds
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Odis Asa Nation
* Leif Rory Reily
* Elmo Asa Raymer
* Hai Solomon Ihm
* Chi Derek Emick
* Daryl Al Ilardi
* Arlie Rey Emlay
* Chi Derek Enick
* Trevor O Howeth
* Louie Pete Hult
* Chet Asa Kazeck
* Shane Pete Kast
* M Vernon Ingemi
* Neil Asa Garing
* Shane Leo Eraso
* Israel E Gehrig
* Elijah Asa Fies
* Chi Derek Erick
* Trevor O Horeth
* Chi Derek Evick
* L Vernon Angela
* Elmo Adan Aumen
* Shane Peter Ast
* Elmo Alan Aumen
* Elmo Alan Armen
* Elmo Adan Armen
* Duane Reyes Ady
* Blake Peter Abt
* Chase Reyes Acy
* Derick C Acorda
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Elijah Asa Dies
* Shelby Bob Deso
* Royce Les Eayrs
* Chi Derek Elick
* Ali Keven Elian
* Royce Wes Eayrs
* Al Steven Ehsan
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* L Royce Cachola
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Arlie Gene Clan
* Arlie Rene Clan
* Cleo Asa Kazeck
* Dean Rory Roady
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elmo Rory Romey
* Ed Luigi Rigler
* Ed Luigi Ridler
* Doug Rory Rhudy
* Dino Rory Rondy
* Dong Rory Rondy
* Truman Asa Ruts
* Dana Rory Randy
* Dane Rory Randy
* Dino Rory Randy
* Dong Rory Randy
* Benito Ty Tunby
* Noel Asa Talent
* E Otha Vanasten
* Elijah Asa Wies
* N Mike Wedekind
* Ali Gene Setias
* Ali Jere Setias
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Louie Pete Sult
* Leo Dana Tabolt
* Leon Asa Tabolt
* Ed Luigi Sirles
* Al Teodoro Star
* Shelby Bob Leso
* Elijah Asa Lies
* Robt Lyle Libre
* Arlie Keven Lav
* Gino Lyle Lynge
* C Mike Mehelich
* Daryl Eli Lordi
* Gino Lyle Longe
* Daryl Ali Lordi
* Gary Lyle Lorge
* Cletus U Kubeck
* Duane Pete Ladt
* Robt Lyle Labre
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Kurt Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Shane Pete Last
* Dino Lyle Lande
* Dana Lyle Lande
* Dirk Lyle Larde
* Dong Lyle Lande
* Santo Coy Ounsy
* Morgan Asa Orms
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raimer
* Elijah Asa Pies
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Odis Asa Nacion
* Otis Asa Nacion
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* Elroy Ty Nygren
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5676 "PBFred"] ==
* Evil Anal Aziel
== From doranchak [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=30#p22403 (1)] [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=40#p22438 (2)]==
* A McNamara Scar
* Ate severed ear
* Trove Behemoth
* Spiro Motorist
* Laura Catapult
* Alice Venetian
* Agile Venetian
* Lebanon Enable
* Indiana Saudis
* Extras Adopted
* Athlete Lethal
* Achieve Lethal
* a Fine Venetian
* of Flanagan Fog
* to One Behemoth
* Extras Adapted
* Training Neat
* Chinese Eel Ice
* Artists Use Tau
* Our Bananas Ron
* Its Revered Sir
* Our Faraway Row
* Old Bikinis Don
* Of These Men Tom (or Of The Semen Tom)
* Greats To The Go
* Or I Was A Nation
* O He Was A Face Of
* [http://www.zodiackillerciphers.com/?p=152 Over 2,700 phrases from Project Gutenberg experiment]
* [https://docs.google.com/spreadsheets/d/13R16xILq6XIWTklErwZq7ltod7EG08-zeiG0AnAtsl4/edit?usp=sharing Another Project Gutenberg experiment, scanned 61.5 GB of text]
* [http://www.zodiackillerciphers.com/?p=467 From article], person names:
** Chastity Tracy
** Erica Natalie T
** Islami M Amelia
** Eddie Resendes
** Ernie Zerenner
** Aileen Enerlan
** Chitumu Eunice
** Ariyana Mariam
** Sripada Harish
** Ali Raja Mariam
** Arriaga Laura L
** Duitama David D
** Steve Menezes N
** Arriaza Laura L
** Arizala Maria M
** Adriana Laura L
** Aziz a Zahaniah
* [http://www.zodiackillerciphers.com/?p=467 From article], phrases / word combinations:
** Sarah The Horse
** Uncle Peter Cut
** Achieve Lethal
** Obscene Nelson
** Extreme Reuter
** Emperors Ropes
** Leigh The Haile
** Kane Pops Punks
** Gareth Tot Ergo
** Niece Gene Penn
** Drop Rarer Code
** Door Non-Encode
** Iraq Alan Again
** All Banana Alan
** Alice Venetian
** Laura Catapult
** Afghan Amalgam
** Reassess Scars
** Clara Cataract
** Shannon Encase
** Okinawa Nation
** Indiana Saudis
** Regan Adalard
** Drippy Peptide
** Outlet Erector
** Akira Canadian
** Adriana Marram
** Mary Nina Norma
** Robert Rory Bro
** Smile Pete List
** Mary Tate Terme
** Mary Gags Germs
** Ryan Amaya Gary
** Daniel Eye Andy
** Eats Bobs Bates
** Kill Baby Bulky
** Shit Pipe Poise
** Eric Alan Alien
** Slave Pete Last
** Extra War After
** Murder Eye Army
** Clara Fatal Act
** Encoded Odd CEO
** [http://zodiackillerciphers.com/z13wordsearch-results-2-sorted.txt List of 283 phrases / word combinations that use two words]
** [http://zodiackillerciphers.com/z13wordsearch-results-3-sorted.txt List of 1,283,443 phrases / word combinations that use three words]
* From another corpus test for [https://www.reddit.com/r/ZodiacKiller/comments/axqx4z/z13_my_name_is_cipher/ reddit post]:
** Chief of Africa
** Uncle Peter Cut
** of Hair It Is Hot
** of These Newton
** at Me O Son of Man
** a Wide Venetian
** a Ripe Venetian
** Avis, a Canadian
** India. Was, and Is.
** I Saw Alan Again
** I Was a Man Again
** I Had a Man Again
** Near a Way As Any
** Claus Asks Jack
** Guest at Otsego
** One Has a Name on
** One Had an Axe on
** As if a Canadian
** Oh No It It Is Not
** Is That As Art Is
** Nearer Eden and
** Niagara Day And
** [http://zodiackillerciphers.com/z13-corpus-solutions.txt Full unprocessed results]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4305&p=69616 More results from corpus scanning:]
** So I'm a Satanist
** So I'm a Fatalist (from glurk)
** A Dog, a Cat, a Goat
** or Steve Nelson
** As I Had an Asian
** a Kid: a Canadian
** Emperor's Ropes
** As Real As Auras
** That I Die, I Hate
** One Has a Name on
** I've Had an Axe in
** Spectate These
** if I Was a Nazi in
** I Eat a Banana in
** As I'm a Canadian
** I Was a Canadian
** Leave Helen All
** Edit As an Alien
** Shakalaka Mask
** Shit! a Natalist!
** Shit! a Fatalist!
** Shit! a Satanist!
** Is a Pagan Again
** Extra Caracter
** and Gamal Abdal
** Donut. It Stands.
** Al Is a Canadian
** Reign on Entire
** I've Had a Dane I.D.
** Least It Steals
** Ratio, Do You Try?
** Said As a Taoist

== From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6406 "Deryk"] ==
* Male, Initial: M.T.
== From [https://www.tapatalk.com/groups/zodiackillerfr/my-name-is-zodiac-t2276-s20.html#p139086 "MickCal"] ==
* OL STEVE NELSON
== From [https://discord.com/channels/996952324150931477/996952376894292018/1135335122527342604 "Toad"] ==
* AMIGO COLONIAL
== From [https://discord.com/channels/996952324150931477/996952376894292018/1033254655381217320 "Antisquid42"] ==
* John E. Heresh Jr.
* Donald LeLinde
* Neal O’Donovann
* Doug Lyle Laude
* Chip O. Kozowicz
* Seth Everett Sr.
* Andrew E. Levdal
* Paul Lyle Loupe
* Shiloh Oto List
* Juan O. Corona Jr.
* Frank X. LeLoafe
* Leo Solomon Olm
== From [http://zodiackillerciphers.com/z13_2_word_solutions.txt "rando"] ==
* [http://zodiackillerciphers.com/z13_2_word_solutions.txt 3,142 2-word solutions]

== Partial solution from [http://zodiackiller.21.forumer.com/viewtopic.php?p=119889#119889 "granny101"] ==
* ILLNEVETELLIT ("I'LL NEVER TELL IT", with the "R" missing)
== From [https://www.tapatalk.com/groups/zodiackillerfr/solution-to-the-challenge-t11196.html#p264079 "CipherS0luti0ns"] ==
* SOLVE REVEALS V
* [https://www.tapatalk.com/groups/zodiackillerfr/my-work-on-z13-t10067-s340.html#p268743 ON TV A WAR ACTOR]

== From [https://discord.com/channels/996952324150931477/996952376894292018/1259617636715860028 "Jasper"] ==
* HOPE IT IS IN PHS (PHS assumed to be reference to Presidio Heights, or Presidio Hill School)
== From @samuelpotts5143 (on YouTube) [https://www.tapatalk.com/groups/zodiackillerfr/z13-not-a-traditional-cipher-t10457-s20.html#p234341 (1)] [https://www.tapatalk.com/groups/zodiackillerfr/z13-my-name-is-solution-t10664.html#p233559 (2)]==
* SAM JR DR FROM SF

= Solutions that fit if you first reverse the cipher =

TODO

= Solutions that fit the ciphertext if you permit anagramming =

Rearranging the cipher text significantly reduces the constraints on possible solutions. As [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=20#p13716 "glurk"] points out, anagramming the 13 symbols permits a very large variety of possible solutions, which makes it nearly impossible to validate any given solution derived this way.

Here are some examples of solutions that arise from anagramming:

* [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=40#p13807 Small sampling from "sincos"]
* From doranchak:
** 13-letter English words that have the same letter distribution as the symbols of the cipher:
*** international, participation, concentration, interventions, investigating, participating, inappropriate, investigative, authoritarian, mediterranean, intentionally, accommodation, strengthening, commissioners, differentiate, collaborators, incorporation, unwillingness, mismanagement, superstitious, mathematician, nationalities, instantaneous, nationalistic, inconsistency, choreographer, preponderance, condescending, applicability, contingencies, indeterminate, sarcastically, temperamental, disillusioned, prerequisites, intelligences, irreplaceable, headquartered, reincarnation, proportionate, appropriating, inclusiveness, preservatives, ornamentation, uninteresting, incapacitated, contaminating, irrationality, abolitionists, improprieties, structuralist, sharecroppers, solicitations, intermarriage, arbitrariness, impermissible, disconnection, professorship, scintillating, insufficiency, spectroscopic, satisfactions
** Small sampling of 13-letter surnames that have the same letter distribution as the symbols of the cipher:
*** radhakrishnan, bhattacharjee, villavicencio, chattopadhyay, oluwatobiloba, degraffenreid, knappenberger, brandenburger, hebblethwaite, rathakrishnan, degraffenried, sahasrabuddhe, stamatopoulos, schlegelmilch, sastrowardoyo, konstantinova, muruganantham, thorsteinsson, madhusoodanan, wojciechowicz, hintermeister, klingenberger, vansteenkiste, raveendranath, blankenbiller, messerschmitt, abdollahzadeh, vlaisavljevic, stamatopoulou, giacomantonio, gebregziabher, gardarsdottir, blattenberger, agustiningsih, sverrisdottir, shirmohammadi, reichenbacher, schottenstein, christophoros, javakhishvili, sundareswaran, schiermeister, kaluhiokalani, natsvlishvili, monteferrante, ntakirutimana, derakhshandeh, winternheimer, spangenberger, liechtenstein, heiderscheidt, chandrarathne, shettlesworth
** [http://zodiackillerciphers.com/all-names-z13-list2-sorted.txt A sampling of 69,607 common first-last name combinations] that have the same letter distribution as the symbols of the cipher.
*** [http://zodiackillersite.com/viewtopic.php?p=18552#p18552 (Original broken forum link)]
* From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6376 Tom Voigt]:
** knickerbocker
** [http://zodiackiller.21.forumer.com/viewtopic.php?p=120299#120299 aintgonnatell]
* From [http://www.santarosahitchhikermurders.com/ Deb Silva]:
** [http://en.wikipedia.org/wiki/Bobby_Beausoleil Bob Beausoleil]
* From Anonymous:
** Jimmy Phillips (also credited to [http://zodiackiller.fr.yuku.com/topic/3827/Jimmy-Phillips alanbenjy])
* From Christer Böke:
** Frank Frazetta ([http://zodiackillersite.com/viewtopic.php?f=63&t=1275 Tim Holt] was drawn by Frank Bollle and Frank Frazetta)
** Grant Santiago
* From [https://www.tapatalk.com/groups/zodiackillerfr/simple-solve-for-the-my-name-is-t8738.html#p145360 jaydeezodiachunter]:
** Debbie Faraday

= Solutions that fit if you relax other constraints of the cipher =

Solutions that fit if you allow all three "circled 8" symbols to be wildcards:
* From Michael Kelleher:
** thebigsecrete
Solutions that are produced via multiple operations:
* From [http://www.zodiackillerciphers.com/?p=46 Lyndon Lafferty]:
** NAME GRANT, or NAME IS GRANT
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/detailed-solution-to-z13-and-z32/ Faycal Ziraoui's solution]
A solution that applies the 408 key and interprets some symbols as nulls:
* from [http://zodiackiller.fr.yuku.com/topic/6839/Zodiacs-Name-using-408-Key Rembrandt]:
** ED SHAW
Solutions with one name part in the middle, and another name part split in half and written backwards:
* [http://www.zodiackillersite.com/viewtopic.php?p=69126#p69126 DEBBIE FARADAY]

= Other interpretations =

* "My name is" contains 8 letters. The cipher text contains 8 letters and 5 special symbols. The special symbols contain Zodiac's name and the rest just mean "My name is" (Source: Jeppesen)
* [https://www.tapatalk.com/groups/zodiackillerfr/general-book-discussion-for-hunted-the-zodiac-murd-t10141.html#p197345 "Set addition" interpretation of Z13 by Doug Oswell], resulting in solution: "FROM TED KACZYNS[K]I"
* [https://www.tapatalk.com/groups/zodiackillerfr/paul-astrup-s-theory-meteorological-symbols-challe-t10261.html#p202558 Weather symbols]
* The line after "My name is" is roughly above symbols that resemble "Tom" spelled backwards. (Source: David Cauley via YouTube comments)

Z13 Solutions

2025-04-10T10:20:05Z

Admin: /* From "Jasper" */

= Solutions that fit the ciphertext as is =

This section only shows proposed solutions that fit the cipher text "as is". No anagramming or other re-arrangements are used here, and the cipher is considered to be strictly a substitution cipher. Solutions that permit anagramming are very easy to come by, as there are several billion possible string combinations to choose from. Solutions that do not require anagramming are still numerous, however, which increases the difficulty of knowing which one is correct.

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=50&t=1390&p=24191#p24190 "Quill"] ==
* Eddie Penerden
* Stan T E Case (using "8"s as spaces)
* Greg N A Vega (using "8"s as spaces)

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5677 "glurk"] (homophonic solutions) ==
* Steve Pete West
* Adrian a Harrah
* Shannon E Nease
* Steve Pete Best
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Eddie Gene Oden
* Steve Pete Vest
* Barney E Yearby
* Gene Lyle Lange
* Eddie Gene Eden
* Ed Steven Eisen
* E Alva Vanallen
* Angelo Lyle Gay
* Eddie Rene Oden
* Isreal a Sarris
* Carl Bob Abarca
* Elliot O Roller
* Andre Reyes Day
* Ed Steve Nelsen
* Shane Pete East
* Lee Gene Levell
* Eddie Rene Eden
* Rueben E Segers
* Rueben E Severs
* Eddie Gene Aden
* Eddie Dewey Dew
* Shane Pete Mast
* Ed Steve Reeser
* Ed Steve Reiser
* Lee Rene Levell
* Neal Alan Amann
* Sean Lyle Lease
* Otto Alan Alton
* Otto Alan Acton
* Otto Alan Aston
* Otto Alan Anton
* Eddie Rene Aden
* Lee Jamal Abell
* Andre Gene Adan
* Reed Alan Ahern
* Shane Pete Fast
* Elliot O Yokley
* Elliot O Soules
* Lee Pete Levell
* Ira Lamar Adair
* Neil Lyle Laine
* Teodoro Tom Ott
* Otto Adam Altom
* Noah Alan Amann
* Eddy Alan Alden
* Lee Jewel Ezell
* Cory Bob Abarca
* Andre Rene Adan
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Earle Gene Wren
* Dean Rory Ready
* Dana Bob Obando
* Luis Rory Reily
* Otto Asa Santos
* Eric Asa Rapier
* Gino Lyle Lange
* Eddy Alan Arden
* Kent Lyle Linke
* Andre Dewey Daw
* Eddie Les Eades
* Louie Pete Ault
* Eddie Jewel Dew
* Ian Reyes Ennis
* Edison O Rosier
* Ollie Lee Enloe
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Ira Jamar Adair
* Earle Rene Wren
* Ernie Dewey New
* Lee Jewel Ewell
* Eddie Wes Eades
* Drew Rory Reedy
* Al Isaias Arias
* Ollie Derek Lor
* Cary Bob Abarca
* Emile Gene Lien
* Arlie Dewey Law
* Ollie Dewey Low
* Rob Dewey Embry
* Curt Bob Abarca
* Earl Asa Laurel
* Stefan Asa Hess
* Eddie Reyes Dey
* Eli Dana Rapier
* Dane Bob Obando
* Elmo Rory Ramey
* Lee Jere Levell
* Ali Rufus Urias
* Emile Rene Lien
* Eddie Jere Eder
* Stan Lyle Lease
* Chi Derek Edick
* Earle Gene Oren
* Emile Gene Bien
* Earle Gene Uren
* Arturo Rory Tao
* Otis Asa Nation
* Genaro Rory Ngo
* Dane Lyle Linde
* Dane Lyle Lynde
* Dane Lyle Lunde
* Scot Lyle Loose
* Ali Reyes Elias
* Art Solomon Tam
* Donn Bob Obando
* Dino Bob Obando
* Andre Jewel Daw
* Neal Adan Amann
* Emile Rene Bien
* Otto Adan Alton
* Earle Rene Uren
* Otto Adan Acton
* Earle Rene Oren
* Otto Adan Anton
* Otto Adan Aston
* Dallas Asa Olds
* Erik Asa Rapier
* Reed Adan Ahern
* Ernie Jewel New
* Donn Lyle Linde
* Dino Lyle Linde
* Donn Lyle Lynde
* Dino Lyle Lunde
* Donn Lyle Lunde
* Dino Lyle Lynde
* Dong Bob Obando
* Teodoro Tod Ott
* Stefan Asa Bess
* Noah Adan Amann
* Arlie Jewel Law
* Issac Jc Ocasio
* Arlie Reyes Lay
* Ed Teodoro Ater
* Ollie Jewel Low
* Eddy Adan Alden
* Shad Lyle Lease
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Shon Lyle Loose
* Dong Lyle Lunde
* Ollie Reyes Loy
* Stefan Asa Ness
* Earle Dewey Rew
* Reed Asa Sayers
* Anibal Asa Dias
* Noe Reyes Edens
* Delmar Asa Olds
* Isreal Al Abril
* Isreal Al April
* Earle Reyes Rey
* Ernie Les Eanes
* Eddy Adan Arden
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Ernie Reyes Ney
* Morgan Asa Arms
* Olin Asa Nation
* Lou Solomon Ulm
* Ernie Wes Eanes
* Ernie Rey Edney
* Odis Asa Nation
* Murray Asa Arms
* Noe Reyes Evens
* Ollie Dee Enloe
* Leif Rory Reily
* Elmo Asa Raymer
* Isaiah Asa Sais
* Anibal Asa Bias
* Ollie Jere Flor
* Reed Asa Sagers
* Reed Asa Sauers
* Stefan Asa Vess
* Stefan Asa Jess
* Stefan Asa Gess
* Ezra Asa Laurel
* Erin Asa Rapier
* Emile Jere Mier
* Emile Jere Pier
* Emile Jere Bier
* Earle Jewel Rew
* Emile Jere Wier
* Emile Jere Kier
* Anibal Asa Sias
* Isaias Asa Sais
* Paris Asa Serpa
* Arlie Jere Klar
* Luigi Gil Ifill
* Hai Solomon Ihm
* Darell L Ilardi
* Chi Derek Emick
* Eddie Lee Emdee
* Daryl Al Ilardi
* Arlie Rey Emlay
* Eddie Rene Iden
* Chi Derek Enick
* Earle Rene Hren
* Trevor O Howeth
* Earle Gene Hren
* Duncan Asa Ends
* Danial Asa Ends
* Louie Pete Hult
* Eddie Gene Iden
* Chas Asa Kasack
* Clay Asa Kasack
* Lee Jewel Euell
* Chad Asa Kasack
* Ian Dana Katnik
* Chet Asa Kazeck
* Shane Pete Kast
* Leo Jewel Etoll
* Ian Dana Kamnik
* M Keenan Ingemi
* M Vernon Ingemi
* Ernie Jere Iner
* Eddie Dee Emdee
* Isaias Asa Kais
* Ed Steven Elsen
* Steve Pete Jest
* Isaiah Asa Kais
* Theron O Howeth
* Neil Asa Garing
* Ernie Wes Ennes
* Noah Asa Galang
* Shane Leo Eraso
* Steve Pete Gest
* Emile Jere Gier
* Israel E Gehrig
* N Eugene Genung
* Neal Asa Galang
* Elijah Asa Fies
* Steve Pete Fest
* Eli Peter Etier
* Ed Steven Essen
* Stefan Asa Fess
* Chi Derek Erick
* Ollie Pete Flot
* Earle Pete Fret
* Ernie Ben Ennen
* Emile Jere Hier
* Ernie Len Ennen
* Ernie Ken Ennen
* Theron O Horeth
* Trevor O Horeth
* Lee Bo Holowell
* Chi Derek Evick
* Ernie Les Ennes
* Adrian Asa Gras
* Earle Gene Gren
* Noe Reyes Ewens
* Ollie Jere Glor
* Shad Asa Habash
* Stan Asa Habash
* Earle Rene Gren
* Sean Asa Habash
* Aldo Alan Ardan
* Andy Adan Ardan
* Art Jamal Antal
* Aldo Adan Ardan
* Eli Jamal Ariel
* Elijah Al Ariel
* Andy Alan Ardan
* Dorian Asa Ards
* Leland N Analla
* R Keenan Andera
* Lee Jamal Amell
* Ty Isaiah Amith
* L Vernon Angela
* Antwan Al Antal
* R Vernon Andera
* L Keenan Angela
* Ed Isaias Aries
* Art Jamal Attal
* Elmo Adan Aumen
* Shane Peter Ast
* Antwan Al Attal
* Otto Alan Auton
* Isreal Al Avril
* Elmo Alan Aumen
* Otto Adan Auton
* Elmo Alan Armen
* Norman Asa Arns
* Isreal Asa Aris
* Elmo Adan Armen
* Alva Adan Arvan
* Alva Alan Arvan
* Otto Adan Arton
* Otto Alan Arton
* Otto Adan Afton
* Otto Alan Afton
* Eddie Jere Ader
* Duane Reyes Ady
* Isaias Adam Aid
* Isaias Adan Aid
* Isaiah Adam Aid
* Isaiah Adan Aid
* Lyle Bob Abella
* Blake Peter Abt
* Ira Jamar Abair
* Ira Lamar Abair
* Chase Reyes Acy
* Lee Jamal Adell
* Tobias Asa Abts
* Derick C Acorda
* Otto Adan Aiton
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Aron Adan Aloan
* Aron Alan Aloan
* Amos Adan Aloan
* Amos Alan Aloan
* Arlie Gene Alan
* Arlie Rene Alan
* Otto Alan Aiton
* Nigel Al Alagna
* Cecil Al Alecca
* Al Isaias Alias
* Arlie Jere Alar
* Bradly L Aldaba
* Arlie Jewell Aw
* Emile Jere Dier
* Elijah Asa Dies
* Emile Gene Dien
* Emile Rene Dien
* Rey Reyes Eayrs
* Roy Reyes Eayrs
* Les Dewey Easly
* Ray Reyes Eayrs
* Earl E Deserres
* Eddie Derek Der
* Earle Deserres
* Stefan Asa Dess
* Steve Pete Dest
* Ezra E Deserres
* Shelby Bob Deso
* Royce Les Eayrs
* Eddie Ben Elden
* Eddie Ken Elden
* Eddie Ken Eiden
* Eddie Len Eiden
* Chi Derek Elick
* Lee Solomon Elm
* Eddie Len Elden
* Ali Keven Elian
* Lee Jewel Edell
* Arlie Leo Edlao
* Royce Wes Eayrs
* Ed Steven Ebsen
* Al Steven Ehsan
* Eddie Ben Eiden
* Reuben Ed Efurd
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* Earle Rene Bren
* Robert Rory Bro
* L Rocco Cachola
* L Royce Cachola
* Royce Rene Byrn
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Otto Adan Axton
* Otto Alan Axton
* Adrian Asa Bras
* Earle Gene Bren
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Leo Gene Debold
* Leo Jere Debold
* Isaias Asa Dais
* Andre Derek Dar
* Leonel E Debold
* Lionel E Debold
* Leo Pete Debold
* Leo Rene Debold
* N Royce Cicconi
* Arlie Gene Clan
* N Boyce Cicconi
* N Rocco Cicconi
* Bruce Jere Cubr
* Isaiah Asa Dais
* Arlie Rene Clan
* Arlie Jere Clar
* Cleo Asa Kazeck
* Dean Rory Roady
* Ryan Rory Roary
* Ed Luigi Riller
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elwood O Rohwer
* Elmo Rory Romey
* Ed Luigi Rigler
* Deon Rory Rhody
* Dion Rory Rhody
* Eli Rene Revier
* Eliseo E Revier
* Ed Luigi Ridler
* Drew Rory Riedy
* Doug Rory Rhudy
* Anibal Asa Rias
* Dino Rory Rondy
* Ivan Asa Salais
* Silas Asa Salsa
* Isaiah a Salais
* Isaias a Salais
* Thomas a Sanots
* Troy Asa Sanots
* Alva Asa Salvas
* Denis Asa Sanda
* Ira Dana Salais
* Cesar Ira Rosca
* Drew Rory Ruedy
* Dong Rory Rondy
* Donn Rory Rondy
* Neil Asa Sabins
* Eloy Asa Sagoes
* Truman Asa Ruts
* Emery Ty Ryneer
* Eli Gene Regier
* Eli Jere Regier
* Ryan Rory Reary
* Ed Steve Reaser
* Eliseo E Regier
* Elmo Rory Remey
* Eli Pete Regier
* Eli Rene Regier
* Ezra Rory Rarey
* Dana Rory Randy
* Dane Rory Randy
* Art Dana Rajtar
* Elmo Asa Rammer
* Donn Rory Randy
* Earl Rory Rarey
* Dino Rory Randy
* Dong Rory Randy
* Eli Gene Renier
* Eddy E Resendes
* Stefan Asa Ress
* Ed Dee Resendes
* Eli Jere Revier
* Eli Pete Revier
* Alva Rory Revay
* Eli Gene Revier
* Eddie Resendes
* Eli Rene Renier
* Eliseo E Renier
* Eli Jere Renier
* Eli Pete Renier
* Art Pete Rentar
* Art Rene Rentar
* Art Gene Rentar
* Art Jere Rentar
* Alva Asa Sarvas
* Emmitt Ty Tomey
* Emmett Ty Tumey
* Emile Pete Tiet
* Emmett Ty Tomey
* Isaiah Asa Vais
* Isaias Asa Vais
* Emmitt Ty Tumey
* Benito Ty Tunby
* Emile Jere Tier
* T Dusty Tatsuta
* T Rusty Tatsuta
* Noe Dana Talent
* Noel Asa Talent
* Emile Gene Tien
* Emile Rene Tien
* Stefan Asa Tess
* Steve Pete Test
* E Otha Vanasten
* Elijah Asa Wies
* Isaiah Asa Zais
* Emile Gene Wien
* Emile Rene Wien
* Emile Rene Zien
* Emile Jere Zier
* Isaias Asa Zais
* Emile Gene Zien
* Stefan Asa Wess
* Emile Rene Vien
* Emile Jere Vier
* Anibal Asa Vias
* Emile Gene Vien
* N Mike Wedekind
* Neil E Wedekind
* Isaiah Asa Wais
* Isaias Asa Wais
* Ali Gene Setias
* Ali Jere Setias
* Noe Rene Serens
* Moses Asa Sesma
* Louis Asa Shula
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Noe Pete Serens
* Ezra Asa Sayres
* Rueben E Sebers
* Reed Asa Savers
* Earl Asa Sayres
* Noe Gene Serens
* Noe Jere Serens
* Miles Asa Selma
* Myles Asa Selma
* Emile Gene Sien
* Thad Asa Tabatt
* Tuan Asa Tabatt
* Ed Teodoro Ster
* Louie Pete Sult
* Duane Pete Tadt
* Graham Asa Tags
* Leo Dana Tabolt
* Leon Asa Tabolt
* Antwan Asa Stas
* Al Luigi Sillas
* Ed Luigi Sirles
* Emile Rene Sien
* Emile Jere Sier
* Louis Asa Soula
* Al Teodoro Star
* Ollie Pete Slot
* Edison O Solies
* Shelby Bob Leso
* Stefan Asa Less
* Tony Lyle Lente
* Zane Lyle Lenze
* Bret Lyle Liebe
* Elijah Asa Lies
* Anibal Asa Lias
* Robt Lyle Libre
* King Lyle Lenke
* Lee Dana Layell
* Eddy Lyle Ledee
* Arlie Keven Lav
* Lee Dana Lavell
* Lyle Lyle Lelle
* Kent Lyle Lenke
* Theo Lyle Leete
* Trey Lyle Leete
* Gene Lyle Longe
* Gino Lyle Lynge
* Isaiah Asa Mais
* Cecil Eli Lucci
* Gene Lyle Lynge
* I Otha Masaitis
* C Mike Mehelich
* Isaias Asa Mais
* Eddy a Marander
* Cecil Ali Lucci
* Daryl Eli Lordi
* Earl Lyle Loree
* Gino Lyle Longe
* Daryl Ali Lordi
* Ollie Peter Lot
* Paul Lyle Loupe
* Ezra Lyle Loree
* Gary Lyle Lorge
* Alvaro R Krivak
* Cletus U Kubeck
* W Rocky Knknown
* Adrian Asa Kras
* Duane Pete Ladt
* Isaiah Asa Lais
* Robt Lyle Labre
* Lee Dana Ladell
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Keenan Asa Keks
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Stefan Asa Kess
* Isaias Asa Lais
* Kurt Lyle Larke
* Vern Lyle Larve
* Kirk Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Lee Dana Lasell
* Shane Pete Last
* Karl Lyle Larke
* Dane Lyle Lande
* Dino Lyle Lande
* Elmo Asa Lammel
* Dana Lyle Lande
* Zane Lyle Lanze
* Dirk Lyle Larde
* Dong Lyle Lande
* Donn Lyle Lande
* Stefan Asa Mess
* Genaro R Orengo
* Isreal Asa Oris
* Otto Everett or
* Adrian Asa Oras
* Al Teodoro Otar
* Santo Coy Ounsy
* Morgan Asa Orms
* Murray Asa Orms
* Teodoro O Omoto
* Steve Pete Oest
* Emile Gene Oien
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Leo Solomon Olm
* Emile Rene Oien
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raemer
* Eddy Asa Raider
* Eddy Asa Radder
* Eddy Asa Raeder
* Isaias Asa Rais
* Antwan a Rajtar
* Elmo Asa Raimer
* Isaiah Asa Rais
* Adrian Adan Rad
* Isaias Asa Pais
* Elijah Asa Pies
* Ollie Jewell Ow
* Isaiah Asa Pais
* Rupert Rory Pro
* Adrian Adam Rad
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Isaias a Narain
* Ivan Asa Narain
* Steve Pete Nest
* Ernie Peter Net
* Ed Steve Neisen
* Ed Steve Nessen
* Isaiah a Narain
* Shannon Z Naasz
* Odis Asa Nacion
* Anibal Asa Mias
* Al Luigi Millam
* Otto Asa Nanton
* Ira Dana Narain
* Olin Asa Nacion
* Otis Asa Nacion
* Ernie Keven Nev
* L Damon Odonald
* L Daron Odonald
* L Aaron Odonald
* L Carol Odonald
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* L Jarod Odonald
* Eddie Jere Oder
* Austin I Nissan
* Elliot O Nowlen
* Emile Jere Nier
* Ian Solomon Nim
* Neal Bob Obiano
* Noah Bob Obiano
* Elroy Ty Nygren
* Emery Ty Nyreen
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5733 "glurk"] (non-homophonic solutions) ==
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Angelo Lyle Gay
* Andre Reyes Day
* Shane Pete Mast
* Shane Pete Fast
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Dean Rory Ready
* Luis Rory Reily
* Gino Lyle Lange
* Louie Pete Ault
* Edison O Rosier
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Arlie Dewey Law
* Rob Dewey Embry
* Eli Dana Rapier
* Elmo Rory Ramey
* Ali Rufus Urias
* Chi Derek Edick
* Otis Asa Nation
* Ali Reyes Elias
* Art Solomon Tam
* Andre Jewel Daw
* Dino Lyle Linde
* Dino Lyle Lunde
* Dino Lyle Lynde
* Arlie Reyes Lay
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Dong Lyle Lunde
* Delmar Asa Olds
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Odis Asa Nation
* Leif Rory Reily
* Elmo Asa Raymer
* Hai Solomon Ihm
* Chi Derek Emick
* Daryl Al Ilardi
* Arlie Rey Emlay
* Chi Derek Enick
* Trevor O Howeth
* Louie Pete Hult
* Chet Asa Kazeck
* Shane Pete Kast
* M Vernon Ingemi
* Neil Asa Garing
* Shane Leo Eraso
* Israel E Gehrig
* Elijah Asa Fies
* Chi Derek Erick
* Trevor O Horeth
* Chi Derek Evick
* L Vernon Angela
* Elmo Adan Aumen
* Shane Peter Ast
* Elmo Alan Aumen
* Elmo Alan Armen
* Elmo Adan Armen
* Duane Reyes Ady
* Blake Peter Abt
* Chase Reyes Acy
* Derick C Acorda
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Elijah Asa Dies
* Shelby Bob Deso
* Royce Les Eayrs
* Chi Derek Elick
* Ali Keven Elian
* Royce Wes Eayrs
* Al Steven Ehsan
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* L Royce Cachola
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Arlie Gene Clan
* Arlie Rene Clan
* Cleo Asa Kazeck
* Dean Rory Roady
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elmo Rory Romey
* Ed Luigi Rigler
* Ed Luigi Ridler
* Doug Rory Rhudy
* Dino Rory Rondy
* Dong Rory Rondy
* Truman Asa Ruts
* Dana Rory Randy
* Dane Rory Randy
* Dino Rory Randy
* Dong Rory Randy
* Benito Ty Tunby
* Noel Asa Talent
* E Otha Vanasten
* Elijah Asa Wies
* N Mike Wedekind
* Ali Gene Setias
* Ali Jere Setias
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Louie Pete Sult
* Leo Dana Tabolt
* Leon Asa Tabolt
* Ed Luigi Sirles
* Al Teodoro Star
* Shelby Bob Leso
* Elijah Asa Lies
* Robt Lyle Libre
* Arlie Keven Lav
* Gino Lyle Lynge
* C Mike Mehelich
* Daryl Eli Lordi
* Gino Lyle Longe
* Daryl Ali Lordi
* Gary Lyle Lorge
* Cletus U Kubeck
* Duane Pete Ladt
* Robt Lyle Labre
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Kurt Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Shane Pete Last
* Dino Lyle Lande
* Dana Lyle Lande
* Dirk Lyle Larde
* Dong Lyle Lande
* Santo Coy Ounsy
* Morgan Asa Orms
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raimer
* Elijah Asa Pies
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Odis Asa Nacion
* Otis Asa Nacion
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* Elroy Ty Nygren
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5676 "PBFred"] ==
* Evil Anal Aziel
== From doranchak [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=30#p22403 (1)] [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=40#p22438 (2)]==
* A McNamara Scar
* Ate severed ear
* Trove Behemoth
* Spiro Motorist
* Laura Catapult
* Alice Venetian
* Agile Venetian
* Lebanon Enable
* Indiana Saudis
* Extras Adopted
* Athlete Lethal
* Achieve Lethal
* a Fine Venetian
* of Flanagan Fog
* to One Behemoth
* Extras Adapted
* Training Neat
* Chinese Eel Ice
* Artists Use Tau
* Our Bananas Ron
* Its Revered Sir
* Our Faraway Row
* Old Bikinis Don
* Of These Men Tom (or Of The Semen Tom)
* Greats To The Go
* Or I Was A Nation
* O He Was A Face Of
* [http://www.zodiackillerciphers.com/?p=152 Over 2,700 phrases from Project Gutenberg experiment]
* [https://docs.google.com/spreadsheets/d/13R16xILq6XIWTklErwZq7ltod7EG08-zeiG0AnAtsl4/edit?usp=sharing Another Project Gutenberg experiment, scanned 61.5 GB of text]
* [http://www.zodiackillerciphers.com/?p=467 From article], person names:
** Chastity Tracy
** Erica Natalie T
** Islami M Amelia
** Eddie Resendes
** Ernie Zerenner
** Aileen Enerlan
** Chitumu Eunice
** Ariyana Mariam
** Sripada Harish
** Ali Raja Mariam
** Arriaga Laura L
** Duitama David D
** Steve Menezes N
** Arriaza Laura L
** Arizala Maria M
** Adriana Laura L
** Aziz a Zahaniah
* [http://www.zodiackillerciphers.com/?p=467 From article], phrases / word combinations:
** Sarah The Horse
** Uncle Peter Cut
** Achieve Lethal
** Obscene Nelson
** Extreme Reuter
** Emperors Ropes
** Leigh The Haile
** Kane Pops Punks
** Gareth Tot Ergo
** Niece Gene Penn
** Drop Rarer Code
** Door Non-Encode
** Iraq Alan Again
** All Banana Alan
** Alice Venetian
** Laura Catapult
** Afghan Amalgam
** Reassess Scars
** Clara Cataract
** Shannon Encase
** Okinawa Nation
** Indiana Saudis
** Regan Adalard
** Drippy Peptide
** Outlet Erector
** Akira Canadian
** Adriana Marram
** Mary Nina Norma
** Robert Rory Bro
** Smile Pete List
** Mary Tate Terme
** Mary Gags Germs
** Ryan Amaya Gary
** Daniel Eye Andy
** Eats Bobs Bates
** Kill Baby Bulky
** Shit Pipe Poise
** Eric Alan Alien
** Slave Pete Last
** Extra War After
** Murder Eye Army
** Clara Fatal Act
** Encoded Odd CEO
** [http://zodiackillerciphers.com/z13wordsearch-results-2-sorted.txt List of 283 phrases / word combinations that use two words]
** [http://zodiackillerciphers.com/z13wordsearch-results-3-sorted.txt List of 1,283,443 phrases / word combinations that use three words]
* From another corpus test for [https://www.reddit.com/r/ZodiacKiller/comments/axqx4z/z13_my_name_is_cipher/ reddit post]:
** Chief of Africa
** Uncle Peter Cut
** of Hair It Is Hot
** of These Newton
** at Me O Son of Man
** a Wide Venetian
** a Ripe Venetian
** Avis, a Canadian
** India. Was, and Is.
** I Saw Alan Again
** I Was a Man Again
** I Had a Man Again
** Near a Way As Any
** Claus Asks Jack
** Guest at Otsego
** One Has a Name on
** One Had an Axe on
** As if a Canadian
** Oh No It It Is Not
** Is That As Art Is
** Nearer Eden and
** Niagara Day And
** [http://zodiackillerciphers.com/z13-corpus-solutions.txt Full unprocessed results]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4305&p=69616 More results from corpus scanning:]
** So I'm a Satanist
** So I'm a Fatalist (from glurk)
** A Dog, a Cat, a Goat
** or Steve Nelson
** As I Had an Asian
** a Kid: a Canadian
** Emperor's Ropes
** As Real As Auras
** That I Die, I Hate
** One Has a Name on
** I've Had an Axe in
** Spectate These
** if I Was a Nazi in
** I Eat a Banana in
** As I'm a Canadian
** I Was a Canadian
** Leave Helen All
** Edit As an Alien
** Shakalaka Mask
** Shit! a Natalist!
** Shit! a Fatalist!
** Shit! a Satanist!
** Is a Pagan Again
** Extra Caracter
** and Gamal Abdal
** Donut. It Stands.
** Al Is a Canadian
** Reign on Entire
** I've Had a Dane I.D.
** Least It Steals
** Ratio, Do You Try?
** Said As a Taoist

== From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6406 "Deryk"] ==
* Male, Initial: M.T.
== From [https://www.tapatalk.com/groups/zodiackillerfr/my-name-is-zodiac-t2276-s20.html#p139086 "MickCal"] ==
* OL STEVE NELSON
== From [https://discord.com/channels/996952324150931477/996952376894292018/1135335122527342604 "Toad"] ==
* AMIGO COLONIAL
== From [https://discord.com/channels/996952324150931477/996952376894292018/1033254655381217320 "Antisquid42"] ==
* John E. Heresh Jr.
* Donald LeLinde
* Neal O’Donovann
* Doug Lyle Laude
* Chip O. Kozowicz
* Seth Everett Sr.
* Andrew E. Levdal
* Paul Lyle Loupe
* Shiloh Oto List
* Juan O. Corona Jr.
* Frank X. LeLoafe
* Leo Solomon Olm
== From [http://zodiackillerciphers.com/z13_2_word_solutions.txt "rando"] ==
* [http://zodiackillerciphers.com/z13_2_word_solutions.txt 3,142 2-word solutions]

== Partial solution from [http://zodiackiller.21.forumer.com/viewtopic.php?p=119889#119889 "granny101"] ==
* ILLNEVETELLIT ("I'LL NEVER TELL IT", with the "R" missing)
== From [https://www.tapatalk.com/groups/zodiackillerfr/solution-to-the-challenge-t11196.html#p264079 "CipherS0luti0ns"] ==
* SOLVE REVEALS V
* [https://www.tapatalk.com/groups/zodiackillerfr/my-work-on-z13-t10067-s340.html#p268743 ON TV A WAR ACTOR]

== From [https://discord.com/channels/996952324150931477/996952376894292018/1259617636715860028 "Jasper"] ==
* HOPE IT IS IN PHS (PHS assumed to be reference to Presidio Heights, or Presidio Hill School)
== From [@samuelpotts5143] (on YouTube)
* SAM JR DR FROM SF

= Solutions that fit if you first reverse the cipher =

TODO

= Solutions that fit the ciphertext if you permit anagramming =

Rearranging the cipher text significantly reduces the constraints on possible solutions. As [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=20#p13716 "glurk"] points out, anagramming the 13 symbols permits a very large variety of possible solutions, which makes it nearly impossible to validate any given solution derived this way.

Here are some examples of solutions that arise from anagramming:

* [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=40#p13807 Small sampling from "sincos"]
* From doranchak:
** 13-letter English words that have the same letter distribution as the symbols of the cipher:
*** international, participation, concentration, interventions, investigating, participating, inappropriate, investigative, authoritarian, mediterranean, intentionally, accommodation, strengthening, commissioners, differentiate, collaborators, incorporation, unwillingness, mismanagement, superstitious, mathematician, nationalities, instantaneous, nationalistic, inconsistency, choreographer, preponderance, condescending, applicability, contingencies, indeterminate, sarcastically, temperamental, disillusioned, prerequisites, intelligences, irreplaceable, headquartered, reincarnation, proportionate, appropriating, inclusiveness, preservatives, ornamentation, uninteresting, incapacitated, contaminating, irrationality, abolitionists, improprieties, structuralist, sharecroppers, solicitations, intermarriage, arbitrariness, impermissible, disconnection, professorship, scintillating, insufficiency, spectroscopic, satisfactions
** Small sampling of 13-letter surnames that have the same letter distribution as the symbols of the cipher:
*** radhakrishnan, bhattacharjee, villavicencio, chattopadhyay, oluwatobiloba, degraffenreid, knappenberger, brandenburger, hebblethwaite, rathakrishnan, degraffenried, sahasrabuddhe, stamatopoulos, schlegelmilch, sastrowardoyo, konstantinova, muruganantham, thorsteinsson, madhusoodanan, wojciechowicz, hintermeister, klingenberger, vansteenkiste, raveendranath, blankenbiller, messerschmitt, abdollahzadeh, vlaisavljevic, stamatopoulou, giacomantonio, gebregziabher, gardarsdottir, blattenberger, agustiningsih, sverrisdottir, shirmohammadi, reichenbacher, schottenstein, christophoros, javakhishvili, sundareswaran, schiermeister, kaluhiokalani, natsvlishvili, monteferrante, ntakirutimana, derakhshandeh, winternheimer, spangenberger, liechtenstein, heiderscheidt, chandrarathne, shettlesworth
** [http://zodiackillerciphers.com/all-names-z13-list2-sorted.txt A sampling of 69,607 common first-last name combinations] that have the same letter distribution as the symbols of the cipher.
*** [http://zodiackillersite.com/viewtopic.php?p=18552#p18552 (Original broken forum link)]
* From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6376 Tom Voigt]:
** knickerbocker
** [http://zodiackiller.21.forumer.com/viewtopic.php?p=120299#120299 aintgonnatell]
* From [http://www.santarosahitchhikermurders.com/ Deb Silva]:
** [http://en.wikipedia.org/wiki/Bobby_Beausoleil Bob Beausoleil]
* From Anonymous:
** Jimmy Phillips (also credited to [http://zodiackiller.fr.yuku.com/topic/3827/Jimmy-Phillips alanbenjy])
* From Christer Böke:
** Frank Frazetta ([http://zodiackillersite.com/viewtopic.php?f=63&t=1275 Tim Holt] was drawn by Frank Bollle and Frank Frazetta)
** Grant Santiago
* From [https://www.tapatalk.com/groups/zodiackillerfr/simple-solve-for-the-my-name-is-t8738.html#p145360 jaydeezodiachunter]:
** Debbie Faraday

= Solutions that fit if you relax other constraints of the cipher =

Solutions that fit if you allow all three "circled 8" symbols to be wildcards:
* From Michael Kelleher:
** thebigsecrete
Solutions that are produced via multiple operations:
* From [http://www.zodiackillerciphers.com/?p=46 Lyndon Lafferty]:
** NAME GRANT, or NAME IS GRANT
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/detailed-solution-to-z13-and-z32/ Faycal Ziraoui's solution]
A solution that applies the 408 key and interprets some symbols as nulls:
* from [http://zodiackiller.fr.yuku.com/topic/6839/Zodiacs-Name-using-408-Key Rembrandt]:
** ED SHAW
Solutions with one name part in the middle, and another name part split in half and written backwards:
* [http://www.zodiackillersite.com/viewtopic.php?p=69126#p69126 DEBBIE FARADAY]

= Other interpretations =

* "My name is" contains 8 letters. The cipher text contains 8 letters and 5 special symbols. The special symbols contain Zodiac's name and the rest just mean "My name is" (Source: Jeppesen)
* [https://www.tapatalk.com/groups/zodiackillerfr/general-book-discussion-for-hunted-the-zodiac-murd-t10141.html#p197345 "Set addition" interpretation of Z13 by Doug Oswell], resulting in solution: "FROM TED KACZYNS[K]I"
* [https://www.tapatalk.com/groups/zodiackillerfr/paul-astrup-s-theory-meteorological-symbols-challe-t10261.html#p202558 Weather symbols]
* The line after "My name is" is roughly above symbols that resemble "Tom" spelled backwards. (Source: David Cauley via YouTube comments)

Halloween card

2025-02-24T14:25:51Z

Admin: /* Gang Symbology */

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Animals ===

==== Cattle Brands ====

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

==== Bird / Bat ====

The "Claude" AI gave this interpretation of the image: "This symbol appears to be a simple line drawing resembling a stylized bird or bat shape, with two angled lines forming what could be interpreted as wings, and two dots suggesting eyes."

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."
* [https://forum.zodiackillerciphers.com/community/postid/79587/ A reference to Z340's transposition scheme]

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Gang Symbology ===

* Hell's Angels (unconfirmed / possibly faked)
** [https://www.reddit.com/r/ZodiacKiller/comments/1inpo6c/hells_angels_mc/ Reddit link]
** [https://x.com/candymugs/status/1889068385352233179 @candymugs post 1]
** [https://x.com/candymugs/status/1889122490003140678 @candymugs post 2]
** [https://x.com/candymugs/status/1889457601131266234 @candymugs post 3 (video clip)]
** [https://x.com/candymugs/status/1889472683345166368 @candymugs post 4]

=== Graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Military ===

* Kevin Robert Brooks, whose suspect is Donald Bujok, said VF4 (or just 4F) is a military classification for mentally unfit. [https://discord.com/channels/996952324150931477/996952376894292018/1322755033179357224 (source)]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]
* [https://en.wikipedia.org/wiki/Alchemical_symbol Alchemical symbols]
** Specifically, [https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Aqua_fortis.svg/48px-Aqua_fortis.svg.png the symbol for "Aqua fortis"]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]
* [https://www.tapatalk.com/groups/zodiackillerfr/wide-flange-beam-gaik-t2170.html "GAIK" in Brahmi alphabet]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Halloween card

2025-02-24T14:18:15Z

Admin:

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Animals ===

==== Cattle Brands ====

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

==== Bird / Bat ====

The "Claude" AI gave this interpretation of the image: "This symbol appears to be a simple line drawing resembling a stylized bird or bat shape, with two angled lines forming what could be interpreted as wings, and two dots suggesting eyes."

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."
* [https://forum.zodiackillerciphers.com/community/postid/79587/ A reference to Z340's transposition scheme]

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Gang Symbology ===

=== Graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Military ===

* Kevin Robert Brooks, whose suspect is Donald Bujok, said VF4 (or just 4F) is a military classification for mentally unfit. [https://discord.com/channels/996952324150931477/996952376894292018/1322755033179357224 (source)]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]
* [https://en.wikipedia.org/wiki/Alchemical_symbol Alchemical symbols]
** Specifically, [https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Aqua_fortis.svg/48px-Aqua_fortis.svg.png the symbol for "Aqua fortis"]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]
* [https://www.tapatalk.com/groups/zodiackillerfr/wide-flange-beam-gaik-t2170.html "GAIK" in Brahmi alphabet]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Halloween card

2025-02-24T14:16:05Z

Admin:

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Animals ===

==== Cattle Brands ====

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

==== Bird / Bat ====

The "Claude" AI gave this interpretation of the image: "This symbol appears to be a simple line drawing resembling a stylized bird or bat shape, with two angled lines forming what could be interpreted as wings, and two dots suggesting eyes."

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Military ===

* Kevin Robert Brooks, whose suspect is Donald Bujok, said VF4 (or just 4F) is a military classification for mentally unfit. [https://discord.com/channels/996952324150931477/996952376894292018/1322755033179357224 (source)]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."
* [https://forum.zodiackillerciphers.com/community/postid/79587/ A reference to Z340's transposition scheme]

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]
* [https://www.tapatalk.com/groups/zodiackillerfr/wide-flange-beam-gaik-t2170.html "GAIK" in Brahmi alphabet]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]
* [https://en.wikipedia.org/wiki/Alchemical_symbol Alchemical symbols]
** Specifically, [https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Aqua_fortis.svg/48px-Aqua_fortis.svg.png the symbol for "Aqua fortis"]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Possible graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Z13 Solutions

2025-02-10T14:43:52Z

Admin: /* From "CipherS0luti0ns" */

= Solutions that fit the ciphertext as is =

This section only shows proposed solutions that fit the cipher text "as is". No anagramming or other re-arrangements are used here, and the cipher is considered to be strictly a substitution cipher. Solutions that permit anagramming are very easy to come by, as there are several billion possible string combinations to choose from. Solutions that do not require anagramming are still numerous, however, which increases the difficulty of knowing which one is correct.

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=50&t=1390&p=24191#p24190 "Quill"] ==
* Eddie Penerden
* Stan T E Case (using "8"s as spaces)
* Greg N A Vega (using "8"s as spaces)

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5677 "glurk"] (homophonic solutions) ==
* Steve Pete West
* Adrian a Harrah
* Shannon E Nease
* Steve Pete Best
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Eddie Gene Oden
* Steve Pete Vest
* Barney E Yearby
* Gene Lyle Lange
* Eddie Gene Eden
* Ed Steven Eisen
* E Alva Vanallen
* Angelo Lyle Gay
* Eddie Rene Oden
* Isreal a Sarris
* Carl Bob Abarca
* Elliot O Roller
* Andre Reyes Day
* Ed Steve Nelsen
* Shane Pete East
* Lee Gene Levell
* Eddie Rene Eden
* Rueben E Segers
* Rueben E Severs
* Eddie Gene Aden
* Eddie Dewey Dew
* Shane Pete Mast
* Ed Steve Reeser
* Ed Steve Reiser
* Lee Rene Levell
* Neal Alan Amann
* Sean Lyle Lease
* Otto Alan Alton
* Otto Alan Acton
* Otto Alan Aston
* Otto Alan Anton
* Eddie Rene Aden
* Lee Jamal Abell
* Andre Gene Adan
* Reed Alan Ahern
* Shane Pete Fast
* Elliot O Yokley
* Elliot O Soules
* Lee Pete Levell
* Ira Lamar Adair
* Neil Lyle Laine
* Teodoro Tom Ott
* Otto Adam Altom
* Noah Alan Amann
* Eddy Alan Alden
* Lee Jewel Ezell
* Cory Bob Abarca
* Andre Rene Adan
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Earle Gene Wren
* Dean Rory Ready
* Dana Bob Obando
* Luis Rory Reily
* Otto Asa Santos
* Eric Asa Rapier
* Gino Lyle Lange
* Eddy Alan Arden
* Kent Lyle Linke
* Andre Dewey Daw
* Eddie Les Eades
* Louie Pete Ault
* Eddie Jewel Dew
* Ian Reyes Ennis
* Edison O Rosier
* Ollie Lee Enloe
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Ira Jamar Adair
* Earle Rene Wren
* Ernie Dewey New
* Lee Jewel Ewell
* Eddie Wes Eades
* Drew Rory Reedy
* Al Isaias Arias
* Ollie Derek Lor
* Cary Bob Abarca
* Emile Gene Lien
* Arlie Dewey Law
* Ollie Dewey Low
* Rob Dewey Embry
* Curt Bob Abarca
* Earl Asa Laurel
* Stefan Asa Hess
* Eddie Reyes Dey
* Eli Dana Rapier
* Dane Bob Obando
* Elmo Rory Ramey
* Lee Jere Levell
* Ali Rufus Urias
* Emile Rene Lien
* Eddie Jere Eder
* Stan Lyle Lease
* Chi Derek Edick
* Earle Gene Oren
* Emile Gene Bien
* Earle Gene Uren
* Arturo Rory Tao
* Otis Asa Nation
* Genaro Rory Ngo
* Dane Lyle Linde
* Dane Lyle Lynde
* Dane Lyle Lunde
* Scot Lyle Loose
* Ali Reyes Elias
* Art Solomon Tam
* Donn Bob Obando
* Dino Bob Obando
* Andre Jewel Daw
* Neal Adan Amann
* Emile Rene Bien
* Otto Adan Alton
* Earle Rene Uren
* Otto Adan Acton
* Earle Rene Oren
* Otto Adan Anton
* Otto Adan Aston
* Dallas Asa Olds
* Erik Asa Rapier
* Reed Adan Ahern
* Ernie Jewel New
* Donn Lyle Linde
* Dino Lyle Linde
* Donn Lyle Lynde
* Dino Lyle Lunde
* Donn Lyle Lunde
* Dino Lyle Lynde
* Dong Bob Obando
* Teodoro Tod Ott
* Stefan Asa Bess
* Noah Adan Amann
* Arlie Jewel Law
* Issac Jc Ocasio
* Arlie Reyes Lay
* Ed Teodoro Ater
* Ollie Jewel Low
* Eddy Adan Alden
* Shad Lyle Lease
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Shon Lyle Loose
* Dong Lyle Lunde
* Ollie Reyes Loy
* Stefan Asa Ness
* Earle Dewey Rew
* Reed Asa Sayers
* Anibal Asa Dias
* Noe Reyes Edens
* Delmar Asa Olds
* Isreal Al Abril
* Isreal Al April
* Earle Reyes Rey
* Ernie Les Eanes
* Eddy Adan Arden
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Ernie Reyes Ney
* Morgan Asa Arms
* Olin Asa Nation
* Lou Solomon Ulm
* Ernie Wes Eanes
* Ernie Rey Edney
* Odis Asa Nation
* Murray Asa Arms
* Noe Reyes Evens
* Ollie Dee Enloe
* Leif Rory Reily
* Elmo Asa Raymer
* Isaiah Asa Sais
* Anibal Asa Bias
* Ollie Jere Flor
* Reed Asa Sagers
* Reed Asa Sauers
* Stefan Asa Vess
* Stefan Asa Jess
* Stefan Asa Gess
* Ezra Asa Laurel
* Erin Asa Rapier
* Emile Jere Mier
* Emile Jere Pier
* Emile Jere Bier
* Earle Jewel Rew
* Emile Jere Wier
* Emile Jere Kier
* Anibal Asa Sias
* Isaias Asa Sais
* Paris Asa Serpa
* Arlie Jere Klar
* Luigi Gil Ifill
* Hai Solomon Ihm
* Darell L Ilardi
* Chi Derek Emick
* Eddie Lee Emdee
* Daryl Al Ilardi
* Arlie Rey Emlay
* Eddie Rene Iden
* Chi Derek Enick
* Earle Rene Hren
* Trevor O Howeth
* Earle Gene Hren
* Duncan Asa Ends
* Danial Asa Ends
* Louie Pete Hult
* Eddie Gene Iden
* Chas Asa Kasack
* Clay Asa Kasack
* Lee Jewel Euell
* Chad Asa Kasack
* Ian Dana Katnik
* Chet Asa Kazeck
* Shane Pete Kast
* Leo Jewel Etoll
* Ian Dana Kamnik
* M Keenan Ingemi
* M Vernon Ingemi
* Ernie Jere Iner
* Eddie Dee Emdee
* Isaias Asa Kais
* Ed Steven Elsen
* Steve Pete Jest
* Isaiah Asa Kais
* Theron O Howeth
* Neil Asa Garing
* Ernie Wes Ennes
* Noah Asa Galang
* Shane Leo Eraso
* Steve Pete Gest
* Emile Jere Gier
* Israel E Gehrig
* N Eugene Genung
* Neal Asa Galang
* Elijah Asa Fies
* Steve Pete Fest
* Eli Peter Etier
* Ed Steven Essen
* Stefan Asa Fess
* Chi Derek Erick
* Ollie Pete Flot
* Earle Pete Fret
* Ernie Ben Ennen
* Emile Jere Hier
* Ernie Len Ennen
* Ernie Ken Ennen
* Theron O Horeth
* Trevor O Horeth
* Lee Bo Holowell
* Chi Derek Evick
* Ernie Les Ennes
* Adrian Asa Gras
* Earle Gene Gren
* Noe Reyes Ewens
* Ollie Jere Glor
* Shad Asa Habash
* Stan Asa Habash
* Earle Rene Gren
* Sean Asa Habash
* Aldo Alan Ardan
* Andy Adan Ardan
* Art Jamal Antal
* Aldo Adan Ardan
* Eli Jamal Ariel
* Elijah Al Ariel
* Andy Alan Ardan
* Dorian Asa Ards
* Leland N Analla
* R Keenan Andera
* Lee Jamal Amell
* Ty Isaiah Amith
* L Vernon Angela
* Antwan Al Antal
* R Vernon Andera
* L Keenan Angela
* Ed Isaias Aries
* Art Jamal Attal
* Elmo Adan Aumen
* Shane Peter Ast
* Antwan Al Attal
* Otto Alan Auton
* Isreal Al Avril
* Elmo Alan Aumen
* Otto Adan Auton
* Elmo Alan Armen
* Norman Asa Arns
* Isreal Asa Aris
* Elmo Adan Armen
* Alva Adan Arvan
* Alva Alan Arvan
* Otto Adan Arton
* Otto Alan Arton
* Otto Adan Afton
* Otto Alan Afton
* Eddie Jere Ader
* Duane Reyes Ady
* Isaias Adam Aid
* Isaias Adan Aid
* Isaiah Adam Aid
* Isaiah Adan Aid
* Lyle Bob Abella
* Blake Peter Abt
* Ira Jamar Abair
* Ira Lamar Abair
* Chase Reyes Acy
* Lee Jamal Adell
* Tobias Asa Abts
* Derick C Acorda
* Otto Adan Aiton
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Aron Adan Aloan
* Aron Alan Aloan
* Amos Adan Aloan
* Amos Alan Aloan
* Arlie Gene Alan
* Arlie Rene Alan
* Otto Alan Aiton
* Nigel Al Alagna
* Cecil Al Alecca
* Al Isaias Alias
* Arlie Jere Alar
* Bradly L Aldaba
* Arlie Jewell Aw
* Emile Jere Dier
* Elijah Asa Dies
* Emile Gene Dien
* Emile Rene Dien
* Rey Reyes Eayrs
* Roy Reyes Eayrs
* Les Dewey Easly
* Ray Reyes Eayrs
* Earl E Deserres
* Eddie Derek Der
* Earle Deserres
* Stefan Asa Dess
* Steve Pete Dest
* Ezra E Deserres
* Shelby Bob Deso
* Royce Les Eayrs
* Eddie Ben Elden
* Eddie Ken Elden
* Eddie Ken Eiden
* Eddie Len Eiden
* Chi Derek Elick
* Lee Solomon Elm
* Eddie Len Elden
* Ali Keven Elian
* Lee Jewel Edell
* Arlie Leo Edlao
* Royce Wes Eayrs
* Ed Steven Ebsen
* Al Steven Ehsan
* Eddie Ben Eiden
* Reuben Ed Efurd
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* Earle Rene Bren
* Robert Rory Bro
* L Rocco Cachola
* L Royce Cachola
* Royce Rene Byrn
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Otto Adan Axton
* Otto Alan Axton
* Adrian Asa Bras
* Earle Gene Bren
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Leo Gene Debold
* Leo Jere Debold
* Isaias Asa Dais
* Andre Derek Dar
* Leonel E Debold
* Lionel E Debold
* Leo Pete Debold
* Leo Rene Debold
* N Royce Cicconi
* Arlie Gene Clan
* N Boyce Cicconi
* N Rocco Cicconi
* Bruce Jere Cubr
* Isaiah Asa Dais
* Arlie Rene Clan
* Arlie Jere Clar
* Cleo Asa Kazeck
* Dean Rory Roady
* Ryan Rory Roary
* Ed Luigi Riller
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elwood O Rohwer
* Elmo Rory Romey
* Ed Luigi Rigler
* Deon Rory Rhody
* Dion Rory Rhody
* Eli Rene Revier
* Eliseo E Revier
* Ed Luigi Ridler
* Drew Rory Riedy
* Doug Rory Rhudy
* Anibal Asa Rias
* Dino Rory Rondy
* Ivan Asa Salais
* Silas Asa Salsa
* Isaiah a Salais
* Isaias a Salais
* Thomas a Sanots
* Troy Asa Sanots
* Alva Asa Salvas
* Denis Asa Sanda
* Ira Dana Salais
* Cesar Ira Rosca
* Drew Rory Ruedy
* Dong Rory Rondy
* Donn Rory Rondy
* Neil Asa Sabins
* Eloy Asa Sagoes
* Truman Asa Ruts
* Emery Ty Ryneer
* Eli Gene Regier
* Eli Jere Regier
* Ryan Rory Reary
* Ed Steve Reaser
* Eliseo E Regier
* Elmo Rory Remey
* Eli Pete Regier
* Eli Rene Regier
* Ezra Rory Rarey
* Dana Rory Randy
* Dane Rory Randy
* Art Dana Rajtar
* Elmo Asa Rammer
* Donn Rory Randy
* Earl Rory Rarey
* Dino Rory Randy
* Dong Rory Randy
* Eli Gene Renier
* Eddy E Resendes
* Stefan Asa Ress
* Ed Dee Resendes
* Eli Jere Revier
* Eli Pete Revier
* Alva Rory Revay
* Eli Gene Revier
* Eddie Resendes
* Eli Rene Renier
* Eliseo E Renier
* Eli Jere Renier
* Eli Pete Renier
* Art Pete Rentar
* Art Rene Rentar
* Art Gene Rentar
* Art Jere Rentar
* Alva Asa Sarvas
* Emmitt Ty Tomey
* Emmett Ty Tumey
* Emile Pete Tiet
* Emmett Ty Tomey
* Isaiah Asa Vais
* Isaias Asa Vais
* Emmitt Ty Tumey
* Benito Ty Tunby
* Emile Jere Tier
* T Dusty Tatsuta
* T Rusty Tatsuta
* Noe Dana Talent
* Noel Asa Talent
* Emile Gene Tien
* Emile Rene Tien
* Stefan Asa Tess
* Steve Pete Test
* E Otha Vanasten
* Elijah Asa Wies
* Isaiah Asa Zais
* Emile Gene Wien
* Emile Rene Wien
* Emile Rene Zien
* Emile Jere Zier
* Isaias Asa Zais
* Emile Gene Zien
* Stefan Asa Wess
* Emile Rene Vien
* Emile Jere Vier
* Anibal Asa Vias
* Emile Gene Vien
* N Mike Wedekind
* Neil E Wedekind
* Isaiah Asa Wais
* Isaias Asa Wais
* Ali Gene Setias
* Ali Jere Setias
* Noe Rene Serens
* Moses Asa Sesma
* Louis Asa Shula
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Noe Pete Serens
* Ezra Asa Sayres
* Rueben E Sebers
* Reed Asa Savers
* Earl Asa Sayres
* Noe Gene Serens
* Noe Jere Serens
* Miles Asa Selma
* Myles Asa Selma
* Emile Gene Sien
* Thad Asa Tabatt
* Tuan Asa Tabatt
* Ed Teodoro Ster
* Louie Pete Sult
* Duane Pete Tadt
* Graham Asa Tags
* Leo Dana Tabolt
* Leon Asa Tabolt
* Antwan Asa Stas
* Al Luigi Sillas
* Ed Luigi Sirles
* Emile Rene Sien
* Emile Jere Sier
* Louis Asa Soula
* Al Teodoro Star
* Ollie Pete Slot
* Edison O Solies
* Shelby Bob Leso
* Stefan Asa Less
* Tony Lyle Lente
* Zane Lyle Lenze
* Bret Lyle Liebe
* Elijah Asa Lies
* Anibal Asa Lias
* Robt Lyle Libre
* King Lyle Lenke
* Lee Dana Layell
* Eddy Lyle Ledee
* Arlie Keven Lav
* Lee Dana Lavell
* Lyle Lyle Lelle
* Kent Lyle Lenke
* Theo Lyle Leete
* Trey Lyle Leete
* Gene Lyle Longe
* Gino Lyle Lynge
* Isaiah Asa Mais
* Cecil Eli Lucci
* Gene Lyle Lynge
* I Otha Masaitis
* C Mike Mehelich
* Isaias Asa Mais
* Eddy a Marander
* Cecil Ali Lucci
* Daryl Eli Lordi
* Earl Lyle Loree
* Gino Lyle Longe
* Daryl Ali Lordi
* Ollie Peter Lot
* Paul Lyle Loupe
* Ezra Lyle Loree
* Gary Lyle Lorge
* Alvaro R Krivak
* Cletus U Kubeck
* W Rocky Knknown
* Adrian Asa Kras
* Duane Pete Ladt
* Isaiah Asa Lais
* Robt Lyle Labre
* Lee Dana Ladell
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Keenan Asa Keks
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Stefan Asa Kess
* Isaias Asa Lais
* Kurt Lyle Larke
* Vern Lyle Larve
* Kirk Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Lee Dana Lasell
* Shane Pete Last
* Karl Lyle Larke
* Dane Lyle Lande
* Dino Lyle Lande
* Elmo Asa Lammel
* Dana Lyle Lande
* Zane Lyle Lanze
* Dirk Lyle Larde
* Dong Lyle Lande
* Donn Lyle Lande
* Stefan Asa Mess
* Genaro R Orengo
* Isreal Asa Oris
* Otto Everett or
* Adrian Asa Oras
* Al Teodoro Otar
* Santo Coy Ounsy
* Morgan Asa Orms
* Murray Asa Orms
* Teodoro O Omoto
* Steve Pete Oest
* Emile Gene Oien
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Leo Solomon Olm
* Emile Rene Oien
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raemer
* Eddy Asa Raider
* Eddy Asa Radder
* Eddy Asa Raeder
* Isaias Asa Rais
* Antwan a Rajtar
* Elmo Asa Raimer
* Isaiah Asa Rais
* Adrian Adan Rad
* Isaias Asa Pais
* Elijah Asa Pies
* Ollie Jewell Ow
* Isaiah Asa Pais
* Rupert Rory Pro
* Adrian Adam Rad
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Isaias a Narain
* Ivan Asa Narain
* Steve Pete Nest
* Ernie Peter Net
* Ed Steve Neisen
* Ed Steve Nessen
* Isaiah a Narain
* Shannon Z Naasz
* Odis Asa Nacion
* Anibal Asa Mias
* Al Luigi Millam
* Otto Asa Nanton
* Ira Dana Narain
* Olin Asa Nacion
* Otis Asa Nacion
* Ernie Keven Nev
* L Damon Odonald
* L Daron Odonald
* L Aaron Odonald
* L Carol Odonald
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* L Jarod Odonald
* Eddie Jere Oder
* Austin I Nissan
* Elliot O Nowlen
* Emile Jere Nier
* Ian Solomon Nim
* Neal Bob Obiano
* Noah Bob Obiano
* Elroy Ty Nygren
* Emery Ty Nyreen
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5733 "glurk"] (non-homophonic solutions) ==
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Angelo Lyle Gay
* Andre Reyes Day
* Shane Pete Mast
* Shane Pete Fast
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Dean Rory Ready
* Luis Rory Reily
* Gino Lyle Lange
* Louie Pete Ault
* Edison O Rosier
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Arlie Dewey Law
* Rob Dewey Embry
* Eli Dana Rapier
* Elmo Rory Ramey
* Ali Rufus Urias
* Chi Derek Edick
* Otis Asa Nation
* Ali Reyes Elias
* Art Solomon Tam
* Andre Jewel Daw
* Dino Lyle Linde
* Dino Lyle Lunde
* Dino Lyle Lynde
* Arlie Reyes Lay
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Dong Lyle Lunde
* Delmar Asa Olds
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Odis Asa Nation
* Leif Rory Reily
* Elmo Asa Raymer
* Hai Solomon Ihm
* Chi Derek Emick
* Daryl Al Ilardi
* Arlie Rey Emlay
* Chi Derek Enick
* Trevor O Howeth
* Louie Pete Hult
* Chet Asa Kazeck
* Shane Pete Kast
* M Vernon Ingemi
* Neil Asa Garing
* Shane Leo Eraso
* Israel E Gehrig
* Elijah Asa Fies
* Chi Derek Erick
* Trevor O Horeth
* Chi Derek Evick
* L Vernon Angela
* Elmo Adan Aumen
* Shane Peter Ast
* Elmo Alan Aumen
* Elmo Alan Armen
* Elmo Adan Armen
* Duane Reyes Ady
* Blake Peter Abt
* Chase Reyes Acy
* Derick C Acorda
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Elijah Asa Dies
* Shelby Bob Deso
* Royce Les Eayrs
* Chi Derek Elick
* Ali Keven Elian
* Royce Wes Eayrs
* Al Steven Ehsan
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* L Royce Cachola
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Arlie Gene Clan
* Arlie Rene Clan
* Cleo Asa Kazeck
* Dean Rory Roady
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elmo Rory Romey
* Ed Luigi Rigler
* Ed Luigi Ridler
* Doug Rory Rhudy
* Dino Rory Rondy
* Dong Rory Rondy
* Truman Asa Ruts
* Dana Rory Randy
* Dane Rory Randy
* Dino Rory Randy
* Dong Rory Randy
* Benito Ty Tunby
* Noel Asa Talent
* E Otha Vanasten
* Elijah Asa Wies
* N Mike Wedekind
* Ali Gene Setias
* Ali Jere Setias
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Louie Pete Sult
* Leo Dana Tabolt
* Leon Asa Tabolt
* Ed Luigi Sirles
* Al Teodoro Star
* Shelby Bob Leso
* Elijah Asa Lies
* Robt Lyle Libre
* Arlie Keven Lav
* Gino Lyle Lynge
* C Mike Mehelich
* Daryl Eli Lordi
* Gino Lyle Longe
* Daryl Ali Lordi
* Gary Lyle Lorge
* Cletus U Kubeck
* Duane Pete Ladt
* Robt Lyle Labre
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Kurt Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Shane Pete Last
* Dino Lyle Lande
* Dana Lyle Lande
* Dirk Lyle Larde
* Dong Lyle Lande
* Santo Coy Ounsy
* Morgan Asa Orms
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raimer
* Elijah Asa Pies
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Odis Asa Nacion
* Otis Asa Nacion
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* Elroy Ty Nygren
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5676 "PBFred"] ==
* Evil Anal Aziel
== From doranchak [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=30#p22403 (1)] [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=40#p22438 (2)]==
* A McNamara Scar
* Ate severed ear
* Trove Behemoth
* Spiro Motorist
* Laura Catapult
* Alice Venetian
* Agile Venetian
* Lebanon Enable
* Indiana Saudis
* Extras Adopted
* Athlete Lethal
* Achieve Lethal
* a Fine Venetian
* of Flanagan Fog
* to One Behemoth
* Extras Adapted
* Training Neat
* Chinese Eel Ice
* Artists Use Tau
* Our Bananas Ron
* Its Revered Sir
* Our Faraway Row
* Old Bikinis Don
* Of These Men Tom (or Of The Semen Tom)
* Greats To The Go
* Or I Was A Nation
* O He Was A Face Of
* [http://www.zodiackillerciphers.com/?p=152 Over 2,700 phrases from Project Gutenberg experiment]
* [https://docs.google.com/spreadsheets/d/13R16xILq6XIWTklErwZq7ltod7EG08-zeiG0AnAtsl4/edit?usp=sharing Another Project Gutenberg experiment, scanned 61.5 GB of text]
* [http://www.zodiackillerciphers.com/?p=467 From article], person names:
** Chastity Tracy
** Erica Natalie T
** Islami M Amelia
** Eddie Resendes
** Ernie Zerenner
** Aileen Enerlan
** Chitumu Eunice
** Ariyana Mariam
** Sripada Harish
** Ali Raja Mariam
** Arriaga Laura L
** Duitama David D
** Steve Menezes N
** Arriaza Laura L
** Arizala Maria M
** Adriana Laura L
** Aziz a Zahaniah
* [http://www.zodiackillerciphers.com/?p=467 From article], phrases / word combinations:
** Sarah The Horse
** Uncle Peter Cut
** Achieve Lethal
** Obscene Nelson
** Extreme Reuter
** Emperors Ropes
** Leigh The Haile
** Kane Pops Punks
** Gareth Tot Ergo
** Niece Gene Penn
** Drop Rarer Code
** Door Non-Encode
** Iraq Alan Again
** All Banana Alan
** Alice Venetian
** Laura Catapult
** Afghan Amalgam
** Reassess Scars
** Clara Cataract
** Shannon Encase
** Okinawa Nation
** Indiana Saudis
** Regan Adalard
** Drippy Peptide
** Outlet Erector
** Akira Canadian
** Adriana Marram
** Mary Nina Norma
** Robert Rory Bro
** Smile Pete List
** Mary Tate Terme
** Mary Gags Germs
** Ryan Amaya Gary
** Daniel Eye Andy
** Eats Bobs Bates
** Kill Baby Bulky
** Shit Pipe Poise
** Eric Alan Alien
** Slave Pete Last
** Extra War After
** Murder Eye Army
** Clara Fatal Act
** Encoded Odd CEO
** [http://zodiackillerciphers.com/z13wordsearch-results-2-sorted.txt List of 283 phrases / word combinations that use two words]
** [http://zodiackillerciphers.com/z13wordsearch-results-3-sorted.txt List of 1,283,443 phrases / word combinations that use three words]
* From another corpus test for [https://www.reddit.com/r/ZodiacKiller/comments/axqx4z/z13_my_name_is_cipher/ reddit post]:
** Chief of Africa
** Uncle Peter Cut
** of Hair It Is Hot
** of These Newton
** at Me O Son of Man
** a Wide Venetian
** a Ripe Venetian
** Avis, a Canadian
** India. Was, and Is.
** I Saw Alan Again
** I Was a Man Again
** I Had a Man Again
** Near a Way As Any
** Claus Asks Jack
** Guest at Otsego
** One Has a Name on
** One Had an Axe on
** As if a Canadian
** Oh No It It Is Not
** Is That As Art Is
** Nearer Eden and
** Niagara Day And
** [http://zodiackillerciphers.com/z13-corpus-solutions.txt Full unprocessed results]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4305&p=69616 More results from corpus scanning:]
** So I'm a Satanist
** So I'm a Fatalist (from glurk)
** A Dog, a Cat, a Goat
** or Steve Nelson
** As I Had an Asian
** a Kid: a Canadian
** Emperor's Ropes
** As Real As Auras
** That I Die, I Hate
** One Has a Name on
** I've Had an Axe in
** Spectate These
** if I Was a Nazi in
** I Eat a Banana in
** As I'm a Canadian
** I Was a Canadian
** Leave Helen All
** Edit As an Alien
** Shakalaka Mask
** Shit! a Natalist!
** Shit! a Fatalist!
** Shit! a Satanist!
** Is a Pagan Again
** Extra Caracter
** and Gamal Abdal
** Donut. It Stands.
** Al Is a Canadian
** Reign on Entire
** I've Had a Dane I.D.
** Least It Steals
** Ratio, Do You Try?
** Said As a Taoist

== From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6406 "Deryk"] ==
* Male, Initial: M.T.
== From [https://www.tapatalk.com/groups/zodiackillerfr/my-name-is-zodiac-t2276-s20.html#p139086 "MickCal"] ==
* OL STEVE NELSON
== From [https://discord.com/channels/996952324150931477/996952376894292018/1135335122527342604 "Toad"] ==
* AMIGO COLONIAL
== From [https://discord.com/channels/996952324150931477/996952376894292018/1033254655381217320 "Antisquid42"] ==
* John E. Heresh Jr.
* Donald LeLinde
* Neal O’Donovann
* Doug Lyle Laude
* Chip O. Kozowicz
* Seth Everett Sr.
* Andrew E. Levdal
* Paul Lyle Loupe
* Shiloh Oto List
* Juan O. Corona Jr.
* Frank X. LeLoafe
* Leo Solomon Olm
== From [http://zodiackillerciphers.com/z13_2_word_solutions.txt "rando"] ==
* [http://zodiackillerciphers.com/z13_2_word_solutions.txt 3,142 2-word solutions]

== Partial solution from [http://zodiackiller.21.forumer.com/viewtopic.php?p=119889#119889 "granny101"] ==
* ILLNEVETELLIT ("I'LL NEVER TELL IT", with the "R" missing)
== From [https://www.tapatalk.com/groups/zodiackillerfr/solution-to-the-challenge-t11196.html#p264079 "CipherS0luti0ns"] ==
* SOLVE REVEALS V
* [https://www.tapatalk.com/groups/zodiackillerfr/my-work-on-z13-t10067-s340.html#p268743 ON TV A WAR ACTOR]

== From [https://discord.com/channels/996952324150931477/996952376894292018/1259617636715860028 "Jasper"] ==
* HOPE IT IS IN PHS (PHS assumed to be reference to Presidio Heights, or Presidio Hill School)

= Solutions that fit if you first reverse the cipher =

TODO

= Solutions that fit the ciphertext if you permit anagramming =

Rearranging the cipher text significantly reduces the constraints on possible solutions. As [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=20#p13716 "glurk"] points out, anagramming the 13 symbols permits a very large variety of possible solutions, which makes it nearly impossible to validate any given solution derived this way.

Here are some examples of solutions that arise from anagramming:

* [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=40#p13807 Small sampling from "sincos"]
* From doranchak:
** 13-letter English words that have the same letter distribution as the symbols of the cipher:
*** international, participation, concentration, interventions, investigating, participating, inappropriate, investigative, authoritarian, mediterranean, intentionally, accommodation, strengthening, commissioners, differentiate, collaborators, incorporation, unwillingness, mismanagement, superstitious, mathematician, nationalities, instantaneous, nationalistic, inconsistency, choreographer, preponderance, condescending, applicability, contingencies, indeterminate, sarcastically, temperamental, disillusioned, prerequisites, intelligences, irreplaceable, headquartered, reincarnation, proportionate, appropriating, inclusiveness, preservatives, ornamentation, uninteresting, incapacitated, contaminating, irrationality, abolitionists, improprieties, structuralist, sharecroppers, solicitations, intermarriage, arbitrariness, impermissible, disconnection, professorship, scintillating, insufficiency, spectroscopic, satisfactions
** Small sampling of 13-letter surnames that have the same letter distribution as the symbols of the cipher:
*** radhakrishnan, bhattacharjee, villavicencio, chattopadhyay, oluwatobiloba, degraffenreid, knappenberger, brandenburger, hebblethwaite, rathakrishnan, degraffenried, sahasrabuddhe, stamatopoulos, schlegelmilch, sastrowardoyo, konstantinova, muruganantham, thorsteinsson, madhusoodanan, wojciechowicz, hintermeister, klingenberger, vansteenkiste, raveendranath, blankenbiller, messerschmitt, abdollahzadeh, vlaisavljevic, stamatopoulou, giacomantonio, gebregziabher, gardarsdottir, blattenberger, agustiningsih, sverrisdottir, shirmohammadi, reichenbacher, schottenstein, christophoros, javakhishvili, sundareswaran, schiermeister, kaluhiokalani, natsvlishvili, monteferrante, ntakirutimana, derakhshandeh, winternheimer, spangenberger, liechtenstein, heiderscheidt, chandrarathne, shettlesworth
** [http://zodiackillerciphers.com/all-names-z13-list2-sorted.txt A sampling of 69,607 common first-last name combinations] that have the same letter distribution as the symbols of the cipher.
*** [http://zodiackillersite.com/viewtopic.php?p=18552#p18552 (Original broken forum link)]
* From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6376 Tom Voigt]:
** knickerbocker
** [http://zodiackiller.21.forumer.com/viewtopic.php?p=120299#120299 aintgonnatell]
* From [http://www.santarosahitchhikermurders.com/ Deb Silva]:
** [http://en.wikipedia.org/wiki/Bobby_Beausoleil Bob Beausoleil]
* From Anonymous:
** Jimmy Phillips (also credited to [http://zodiackiller.fr.yuku.com/topic/3827/Jimmy-Phillips alanbenjy])
* From Christer Böke:
** Frank Frazetta ([http://zodiackillersite.com/viewtopic.php?f=63&t=1275 Tim Holt] was drawn by Frank Bollle and Frank Frazetta)
** Grant Santiago
* From [https://www.tapatalk.com/groups/zodiackillerfr/simple-solve-for-the-my-name-is-t8738.html#p145360 jaydeezodiachunter]:
** Debbie Faraday

= Solutions that fit if you relax other constraints of the cipher =

Solutions that fit if you allow all three "circled 8" symbols to be wildcards:
* From Michael Kelleher:
** thebigsecrete
Solutions that are produced via multiple operations:
* From [http://www.zodiackillerciphers.com/?p=46 Lyndon Lafferty]:
** NAME GRANT, or NAME IS GRANT
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/detailed-solution-to-z13-and-z32/ Faycal Ziraoui's solution]
A solution that applies the 408 key and interprets some symbols as nulls:
* from [http://zodiackiller.fr.yuku.com/topic/6839/Zodiacs-Name-using-408-Key Rembrandt]:
** ED SHAW
Solutions with one name part in the middle, and another name part split in half and written backwards:
* [http://www.zodiackillersite.com/viewtopic.php?p=69126#p69126 DEBBIE FARADAY]

= Other interpretations =

* "My name is" contains 8 letters. The cipher text contains 8 letters and 5 special symbols. The special symbols contain Zodiac's name and the rest just mean "My name is" (Source: Jeppesen)
* [https://www.tapatalk.com/groups/zodiackillerfr/general-book-discussion-for-hunted-the-zodiac-murd-t10141.html#p197345 "Set addition" interpretation of Z13 by Doug Oswell], resulting in solution: "FROM TED KACZYNS[K]I"
* [https://www.tapatalk.com/groups/zodiackillerfr/paul-astrup-s-theory-meteorological-symbols-challe-t10261.html#p202558 Weather symbols]
* The line after "My name is" is roughly above symbols that resemble "Tom" spelled backwards. (Source: David Cauley via YouTube comments)

Halloween card

2024-12-30T12:54:19Z

Admin:

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Animals ===

==== Cattle Brands ====

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

==== Bird / Bat ====

The "Claude" AI gave this interpretation of the image: "This symbol appears to be a simple line drawing resembling a stylized bird or bat shape, with two angled lines forming what could be interpreted as wings, and two dots suggesting eyes."

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Military ===

* Kevin Robert Brooks, whose suspect is Donald Bujok, said VF4 (or just 4F) is a military classification for mentally unfit. [https://discord.com/channels/996952324150931477/996952376894292018/1322755033179357224 (source)]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."
* [https://forum.zodiackillerciphers.com/community/postid/79587/ A reference to Z340's transposition scheme]

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]
* [https://www.tapatalk.com/groups/zodiackillerfr/wide-flange-beam-gaik-t2170.html "GAIK" in Brahmi alphabet]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]
* [https://en.wikipedia.org/wiki/Alchemical_symbol Alchemical symbols]
** Specifically, [https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Aqua_fortis.svg/48px-Aqua_fortis.svg.png the symbol for "Aqua fortis"]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Possible graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Miscellaneous case updates and details

2024-12-09T02:19:43Z

Admin:

2024-12-08
* From Tom Voigt: "I know of three confirmed Zodiac letters that have not been released to the public." [https://www.tapatalk.com/groups/zodiackillerfr/newbies-and-others-ask-your-zodiac-questions-here-t8815-s4820.html#p279541 (source)]
2024-07-26
* From Soze: Relating to the October 5, 1970 13 hole punch card that included “The pace isn’t any slower! In fact its just one big thirteenth”. The statement comes from a Smidgens cartoon strip by Robert Lee Cordray dated September 25, 1970. Here is a sampling that shows both Robert Cordray and Darlene Ferrin. [https://discord.com/channels/1260505612131897375/1263467644904800256/1263467646293118986 (source)]
2023-07-24
* [https://www.tapatalk.com/groups/zodiackillerfr/halloween-card-turns-up-in-the-wild-t10977.html Unmodified Halloween card turns up on eBay]
2022-08-14
* [https://www.tapatalk.com/groups/zodiackillerfr/nancy-bennallack-solved-8-10-22-zodiac-t10562-s190.html#p227338 Tom claims police are holding back three authentic Zodiac letters.]
** "Each has something to do with Sacramento. One is the DMV letter and another one or two has something to do with Nancy Bennallack."
2022-08-08
* From [https://discord.com/channels/996952324150931477/996952376894292018/1006054767388278814 Discord discussion] with Tom Voigt:
** Zodiac's Halloween card is postmarked only one day after the first news report of the death of [https://www.kcra.com/article/oldest-sacramento-county-cold-case-solved/40862241 Nancy Bennallack]
** Tom was asked not to mention "one of the items" related to Nancy and the Halloween card.
** "a foreign substance added to the card, plus a confirmed letter from Z apparently referring to nancy"
** "there are apparently three confirmed Zodiac letters not made public, and all have something to do with Sacramento"
** "DMV letter, Nancy letter, and I can't remember the third"
2022-08-05
* [https://www.tapatalk.com/groups/zodiackillerfr/the-2500-t10545.html#p225722 Partial list of cleared suspects], purported to be from an official report.
2022-07-14
* Mac suspect timeline
** [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s23460.html#p222860 Tom's version]
** [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s23470.html#p222881 chriscrozzz' version]
2022-07-12
* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s23180.html#p222346 Mac suspect timeline compared to Zodiac]
2022-07-02
* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s22570.html#p221094 Betty Lou Jensen's niece talks to Morf about Rainbow Girls and Masons]
** [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s22580.html#p221114 2nd post]
2022-06-02
* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s21240.html#p217551 Mystery profile sketch, from Morf]
2022-05-23
* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s20160.html#p215676 Detectives active on Zodiac case, per Tom Voigt]
** Detective Terry Schillinger is temporarily out with an injury at Vallejo PD so Detective Josh Caitham has the case for now.
** Dax West at the Solano County Sheriff's Department.
** Napa County has a cold case unit.
** Gianrico Pierucci was working the case in retirement for SFPD last I heard.
2022-05-21
* [https://www.tapatalk.com/groups/zodiackillerfr/reddit-youtube-zodiac-nonsense-t9369-s1560.html#p214627 Tom's summary of DNA evidence in Cheri Jo Bates case]
** A mitochondrial DNA profile was created based on what was found in Cheri's hand. No match has been found and I don't believe they are looking.
** More recently a nuclear DNA profile was created based on the blood found on her pants. The result? It was not foreign DNA.
** Nuclear DNA can't be compared to mitochondrial DNA.
2022-02-08
* [https://www.youtube.com/watch?v=2Y9RjRxzRRY&t=3606s Donald Harden calls during Tom Voigt et al.'s Crime Con in 2008]
2022-01-18
* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s11780.html#p194276 Montana/Colorado/Deer Lodge reporting timeline by mrseanz]
2022-01-13
* [https://www.tapatalk.com/groups/zodiackillerfr/zodiac-dna-update-dec-20th-2021-t10058-s880.html#p193924 Mike Morford claims there is DNA matching between a 1974 letter and 1969 letter, and that DNA was recovered from a 1978 letter.]
2022-01-11
* [https://www.tapatalk.com/groups/zodiackillerfr/donna-lass-not-a-zodiac-victim-t10062-s70.html#p193571 Letter from Donna Lass to her mother]
2022-01-10
* Mike Morford [https://zodiackiller.net/community/cecelia-shepard-bryan-hartnell-9-27-69/i-talked-to-another-lake-berryessa-witness-this-is-what-he-told-me/ talked to another Lake Berryessa witness]
* Transcription of [https://www.tapatalk.com/groups/zodiackillerfr/donna-lass-not-a-zodiac-victim-t10062-s60.html#p193475 Mary Pilker's report on Donna Lass]
** [https://www.tapatalk.com/groups/zodiackillerfr/donna-lass-not-a-zodiac-victim-t10062-s80.html#p193644 2nd report (not yet transcribed)]
2021-12-29
* Tom Voigt [https://www.tapatalk.com/groups/zodiackillerfr/discussion-chester-clark-klingel-aka-sam-from-eure-t10077.html#p191577 describes DNA ruling out the suspect Chester Clark Klingel]
2021-12-27
* [https://www.tapatalk.com/groups/zodiackillerfr/zodiac-killer-a-new-lead-for-2022-t10073.html Zodiac-like handwriting on old typewriter warranty card]
2021-12-26
* Rocky25's [https://www.tapatalk.com/groups/zodiackillerfr/zodiac-dna-update-dec-20th-2021-t10058-s620.html#p191250 list of suspects whose DNA samples have reportedly been compared to Zodiac's]
2021-12-22
* Tom Voigt [https://www.tapatalk.com/groups/zodiackillerfr/zodiac-dna-update-dec-20th-2021-t10058-s320.html#p190618 implies there is additional undisclosed (to the public) evidence included with Zodiac mailings]
* A BBC documentary [https://www.tapatalk.com/groups/zodiackillerfr/zodiac-dna-update-dec-20th-2021-t10058-s350.html#p190669 claimed a bullet was also included with Stine's bloody shirt]
2021-12-20
* Tom Voigt [https://www.tapatalk.com/groups/zodiackillerfr/dna-update-will-happen-dec-20th-2021-t10058-s40.html#p190267 discloses DNA-related information from unnamed sources.]
** The testing of Zodiac evidence produced a DNA profile. That's the good news. The bad news? The profile belonged to an individual who could not have been the Zodiac killer. That's as specific as I can be. One possibility is the profile belongs to an accomplice. Or an unknowing contributor not involved in the crimes. A major complication is during the Zodiac era, a popular form of civil disobedience was to reuse stamps. All of that is under consideration and the process is continuing.
** The original sample (2002) was of a male and still could belong to the actual Zodiac although it was not located where one would have preferred. [https://www.tapatalk.com/groups/zodiackillerfr/dna-update-will-happen-dec-20th-2021-t10058-s70.html#p190299 (Link)]
2021-12-01: Mike Morford received details from a Lake Berryessa witness. [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s10250.html#p187641 (link 1)] [https://www.tapatalk.com/groups/zodiackillerfr/one-of-the-sunbathing-girls-from-lake-b-chimes-in-t10024.html#p187644 (link 2)]
** Hi Mike, Yes I am THAT ******* a possible witness to the Lake Berryessa killer. I guess maybe some statute of limitations has expired because I've had a few people contact me. My identity and testimony at the time was under the agreement of secrecy as for years I was in fear of being identified and at risk. Obviously that criminal must be long dead by now. You didn't name the photo of the man you sent. And of course, 50 years on, I don't know. There are several photos I have been sent that look like the man I saw. Yes the photo you included very much looks like the man I saw, but your photo shows him quite heavy, and the man I saw was thin. A Frenchman has 'identified' the killer as Lawrence Kane, and the photo is similar to my identikit but I don't feel it's him. There is a 1950s photo of Arthur Leigh Allen, and that 50s photo is very strongly similar to who I saw. Photos of Gary Francis Poste show no resemblance. So there's no real answer I can provide. The man I saw stalked 3 of us girls and followed us to the lake. We sunbathed on the cove right next to where the killings took place, and left an hour or so before the attacks began. The man followed us to the shoreline and observed us from the trees. That's about all I can offer. Good luck with your research!
2012-06-06
* [http://zodiackillerciphers.com/images/prints-napa-sfpd.png Morf reporting what Napa investigators said when asked about comparing Napa prints to SFPD prints.]
2010-04-25
* JDean, reportedly a former VPD cop, on morf's old forum posted details about the children who witnessed the Stine murder. [https://zodiackiller.net/community/paul-stine-10-11-69/the-witnesses/#post-378 (link)] [http://zodiackillerciphers.com/jdean-witness-stories.txt (isolated post)]
2009
* Mike Morford says Ken Narlowe described to him the knife Hartnell saw: "weapon desc as a large knife, blade apprx 12 in long and 1 inch wide wooden handle with two brass rivets, could have been a bayonet. nothing further" [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s18450.html#p213212 (source)]

Encyclopedia of observations

2024-09-05T10:47:56Z

Admin: /* The "Pivots" */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve])

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]
* Z340's alphabet consists of 63 unique symbols. Coincidentally, the lengths of Z18, Z13, and Z32 add up to 63. (source: @rogerverreault8682 on YouTube)

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.
* 9 out of 14 of the plaintext letters forming the pivots involve the letters A, E, or N. In both the 340 and 408 keys, the backwards L symbol decodes to A, the N symbol decodes to E, and the D symbol decodes to N. Those are the only symbols that decode to the same letter. Also, Z13 begins with the same three letters: AEN. [https://www.reddit.com/r/ZodiacExtortion/comments/1f3hqsl/pivot_patterns_with_aen_symbols/ (Source: Sam Fisher)]

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Encyclopedia of observations

2024-09-05T10:45:26Z

Admin: /* The "Pivots" */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve])

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]
* Z340's alphabet consists of 63 unique symbols. Coincidentally, the lengths of Z18, Z13, and Z32 add up to 63. (source: @rogerverreault8682 on YouTube)

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.
* 9 out of 14 of the plaintext letters forming the pivots involve the letters A, E, or N. In both the 340 and 408 keys, the backwards L symbol decodes to A, the N symbol decodes to E, and the D symbol decodes to N. Those are the only symbols that decode to the same letter. [https://www.reddit.com/r/ZodiacExtortion/comments/1f3hqsl/pivot_patterns_with_aen_symbols/ (Source: Sam Fisher)]

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Solution to the 340

2024-08-10T10:41:57Z

Admin: /* "WHERE DEATH IS LIFE" (suggested by Brandon Baskin) */

== Raw text of the solution, after reversing transposition ==

''Presumed errors are in boldface:''

: I HOPE YOU ARE HAVING LOTS OF F'''A'''N IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRING'''O''' UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECA'''A'''SE IT WILL SEND ME TO PARAD'''L'''CE
: ALL THE SOO'''H'''ER BECAUSE '''E''' NOW HAVE ENOUGH SLAVES
: TO WOR'''V''' FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I '''V'''NOW THAT MY NEW
: LIFE IS LIFE WILL BE AN EASY ONE IN PARADICE DEATH

''With errors corrected:''

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE IS LIFE WILL BE AN EASY ONE IN PARADICE DEATH

== Interpretations of the seemingly misplaced words "LIFE IS" and "DEATH" ==

=== Group "LIFE IS" with "DEATH" ===

Example 1:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE WILL BE AN EASY ONE IN PARADICE.
: '''LIFE IS DEATH'''

Example 2:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE WILL BE AN EASY ONE IN PARADICE.
: '''DEATH IS LIFE'''

Example 3:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: '''LIFE IS DEATH'''. LIFE WILL BE AN EASY ONE
: IN PARADICE

Example 4:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH. '''LIFE IS DEATH'''. I AM NOT AFRAID
: BECAUSE I KNOW THAT MY NEW LIFE WILL BE AN EASY
: ONE IN PARADICE

Example 5:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE WILL BE AN EASY ONE: '''DEATH IS LIFE'''
: IN PARADICE.

''Additional speculation: The original ciphertext starts with the letters "HER", so perhaps the intended message formed from these fragments is "HER LIFE IS DEATH".''

=== Change "THAT" to "WHAT" ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW '''WHAT''' MY NEW
: LIFE IS: LIFE WILL BE AN EASY ONE IN PARADICE DEATH

=== "MY DEATH IS NEW LIFE" ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY
: '''DEATH IS NEW LIFE'''. LIFE WILL BE AN EASY ONE
: IN PARADICE

=== "WHERE DEATH IS LIFE" (suggested by Brandon Baskin) ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASNT ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME EVERYONE ELSE HAS NOTHING WHEN THEY
: REACH PARADICE SO THEY ARE AFRAID OF DEATH I AM
: NOT AFRAID BECAUSE I KNOW THAT MY NEW LIFE WILL
: BE AN EASY ONE IN PARADICE '''WHERE DEATH IS LIFE'''

=== "DEATH WILL BE AN EASY ONE" (suggested by @muzutus on YouTube) ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE IS LIFE IN PARADICE
: DEATH WILL BE AN EASY ONE

== Verifications of the solution ==

* FBI confirmations:
** [https://twitter.com/FBISanFrancisco/status/1337477701825925120 FBI statement on their twitter account]
** [https://www.cnet.com/science/zodiac-killer-message-known-as-340-cipher-solved-after-51-years/ Article with excerpt from more detailed FBI statement]
** The full press release that was sent to me from the FBI press office:
*** ''The FBI has a team of cryptanalysis experts that decipher coded messages, symbols, and records from criminals known as the Cryptanalysis and Racketeering Records Unit. CRRU regularly works with the cryptologic research community to solve ciphers. On December 5, 2020, the FBI received the solution to a cipher popularly known as Z340 from a cryptologic researcher and independently verified the decryption. Cipher Z340 is one of four ciphers attributed to the Zodiac Killer. This cipher was first submitted to the FBI Laboratory on November 13, 1969, but not successfully decrypted. Over the past 51 years CRRU has reviewed numerous proposed solutions from the public–none of which had merit. The cipher was recently solved by a team of three private citizens. The Zodiac Killer case remains an ongoing investigation for the FBI San Francisco division and our local law enforcement partners. The Zodiac Killer terrorized multiple communities across Northern California and even though decades have gone by, we continue to seek justice for the victims of these brutal crimes. Due to the ongoing nature of the investigation, and out of respect for the victims and their families, we will not be providing further comment at this time.''
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/why-the-transposition-in-the-340-solution-is-inevitably-correct/#post-86366 f.reichmann's argument based on unicity distance]
*** [https://zodiackillerfacts.com/news-and-updates/breaking-news-the-zodiacs-340-cipher-has-been-solved/ Full FBI press release was included in Michael Butterfield's article]
* [https://www.youtube.com/watch?v=hIrOftXgibg Nils Kopal's verification]
* [https://eprint.iacr.org/2021/1620 ''Unicity distance of the Zodiac-340 cipher'' by Joachim von zur Gathen]

== More info ==

* [https://www.youtube.com/watch?v=-1oQLPRE21o Solution video 1]
* [https://www.youtube.com/watch?v=UfrFSrI05hk Solution video 2]
* [http://zodiackillerciphers.com/images/z340-key.png Image of the Z340 substitution key]
* [[Compilation of news reports about the solution]]
* [http://www.zodiackillerciphers.com/?p=869 Sam's slides] from his presentation, [https://www.youtube.com/watch?v=iuNyQ44JYxM "The Quest to Solve the Zodiac 340 Cipher"].
* [[Transposition matrices]]

== Timeline of arriving at the solution ==
''Times reported are in Eastern time in the USA''
=== Saturday, January 3, 2015 ===
* 05:56PM: [http://www.zodiackillersite.com/viewtopic.php?p=27087#p27087 Jarl's first post about availability of his new codebreaking software, AZdecrypt. (broken link)]
** [https://forum.zodiackillerciphers.com/community/zodiac-cipher-mailings-discussion/azdecrypt-beta-0-94/ Working link]

=== Tuesday, July 28, 2015 ===
* 01:02PM: Jarl posts his observations including period 19 bigram repeats [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (original version in Wayback)] [https://zodiackiller.net/community/postid/39170/ (Live version)]
=== Wednesday, August 5, 2015 ===
* 12:45AM: Daikon posts his observations including period 19 bigram repeats [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (original version in Wayback)] [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ Live version]
=== Wednesday, January 16, 2019 ===
* 09:12AM: Sam Blake's first contact with me, via comment on [https://www.youtube.com/watch?v=3Hk__Hk5c9M my 2018 ACA presentation video on Youtube.]
=== Thursday, August 1, 2019 ===
* 09:14PM: Sam Blake starts emailing me enumerations of Z340

=== Sunday, May 17th, 2020 ===
* 07:03AM: Jarl posts a [https://forum.zodiackillerciphers.com/community/zodiac-cipher-mailings-discussion/z340-multiple-transcription-rectangles/ transposition of the 340] which is extremely close to the correct final result.
** [http://zodiackillerciphers.com/jarl-transposition-3-sections-period-19.txt Transcription]
** [http://zodiackillerciphers.com/jarl-transposition-3-sections-period-19-pt.txt Plaintext resulting from applying final Z340 key to his transposed ciphertext]
** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/z340-multiple-transcription-rectangles/ Old broken link]

=== Wednesday, December 2nd, 2020 ===
* 04:14PM: Began running 655,088 ciphers, the cumulative collection of all cipher enumerations and decimations Sam Blake has sent me to date, through AZDecrypt v1.19 with default settings (except for loading jarlve's reddit 6-grams). Had run many of them before, but this time I wanted to be more careful about sorting the results based on the cipher lengths (some manipulations remove parts of the cipher, which sometimes leads to azdecrypt reporting higher scores compared to ones for ciphers of length 340).
=== Thursday, December 3rd, 2020 ===
* 12:04PM: Reported an interesting result to Sam from one of his older vertical 3-split decimations
** [http://www.zodiackillerciphers.com/z340_vertical_3split_decimations_9_9_1_19_2.txt Transcription: z340_vertical_3split_decimations_9_9_1_19_2.txt]
*** [http://www.zodiackillerciphers.com/z340_vertical_3split_decimations_9_9_1_19_2_pt.txt Plaintext resulting from applying the final Z340 key to his transposed ciphertext]
** AZdecrypt generated this candidate plaintext:
*** EHOPE YOU ARE HE SING IST TORRA ENN
*** TRYING TO CATCH METH AFTAINT MT ON THE
*** TS SHOT WHICH BRINGS UP ALS IN TABS IT
*** ME NAME OF AR HEED OR THE GAS CHAMBER
*** BECA ATE IT WILD VENT ME ROLER A DICE
*** AI I THE VS SHEN BECAUSE TOO WHA SEEN
*** TIGHT DESERTS WORS ROS ME THERE
*** EVERYONEED HE HAS NOTHING THEN THEY HE
*** ACH PARADICT IS THEY ALREARE AND NORDER
*** THER AMEO EARRE AND BECAUITE IS YOT TV
*** HAT MR NEWE ITLE NEVER IND BAEYN NEIA
*** AT A HOE CDR PET
** A few interesting legible phrases stood out right away:
*** HOPE YOU ARE
*** TRYING TO CATCH ME
*** SHOT WHICH BRINGS UP
*** OR THE GAS CHAMBER
*** HE HAS NOTHING THEN THEY
** Phrases were more noticeable due to the auto-whitespace feature Jarl added for v1.19.
* 03:25PM: Determined the transposition (decimation) steps that were performed for that cipher among Sam's batch.
* 07:50PM: Sam provides details on the 9,9,1,19,2 enumeration, which is actually split into 4 vertical groups of size 9, 9, 1, and 1. A decimation of 19,2 is applied to each group.
* 09:36PM: I reported to Sam my solution to the first 9 lines, obtained by isolating those 9 lines, feeding them into AZdecrypt, but locking in cribs for some of the interesting phrases discovered earlier.
** The plaintext read: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO CATCH ME THAT WASNT ME ON THE TV SHOW WHICH BRING OR PA POINT ABOUT ME I UM NOT A FRA IF OF THE GAS CHAMBER BECUASE IT WILL SEND ME TO PAY UNLCE ALL THE
** The first section contains every symbol used in the entire cipher, so applying the key to the entire cipher text gave this plaintext: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO CATCH ME THAT WASNT ME ON THE TV SHOW WHICH BRING OR PA POINT ABOUT ME I UM NOT AFRAID OF THE GAS CHAMBER BECUASE IT WILL SEND ME TO PAY UNLCE ALL THE SOO HEN BE CURSEE OOW HAVE ENSUGH SLAVER TO WOR V FOV ME WHERE ESERYONE EL HEH US NOTHING WHEN THEY REACH PAY UNICE SO TREY ALREU FAA I FI OF NET TH IF AM NO EA FREA IF BNC ARISE IV YO WT SHAT MR NEW EIW LENESE FLIL BAAYNNE I UADAHO I CFR PET
** Appearance of phrase "THAT WASNT ME ON THE TV SHOW" locked this in as a solid lead towards a real solution. Second 9 lines yielded from the same key have a relatively high score (compared to random plaintext or gibberish) but is somewhat garbled. Also noticed the word DEATH appearing at the very end of the last line of the entire cipher, using same key as the one discovered for the first 9 lines. Asked Sam for help to figure out the remaining 11 lines.
* 10:04PM: Notified Jarl to also ask for his help.

=== Friday, December 4rd, 2020 ===
* 08:04AM: Ran several other decimations from Sam to try to isolate other schemes that might lead to a solve for the remaining 11 lines.
* 09:29AM: Completed a search of over 400,000 AZdecrypt results and determined that the phrase GAS CHAMBER appears in no other result.
* 10:10AM: Ran some more decimations from Sam. Didn't notice anything substantial in the results.
* 11:19AM: First response from Jarl, "It looks genuine!"
* 02:17PM: I report reversed words in the last 2 lines to Sam and Jarl
* 02:23PM: Jarl independently reports reversed words in the last 2 lines.
* 02:31PM: I interpreted the garbled 2nd section to read like this:
** BECAUSE ? SLAVES TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF LETTING ?? BECAUSE I (VOW?)...
* 02:40PM: Refined 2nd section:
** BECAUSE ??? HAVE ENOUGH SLAVES TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF LETTING ?? BECAUSE I (VOW?)...
* 02:58PM: Jarl reports his refined solution:
**I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING
**TO CATCH ME THAT WASNT ME ON THE TV SHOW
**WHICH BRINGS UP A POINT ABOUT ME I AM NOT
**AFRAID OF THE GAS CHAMBER BECAUSE IT WILL
**SEND ME TO PARADICE ALL THE
**
**SOO HEN BECAUSE EOOW HAVE ENOUGH SLAVES TO
**WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
**WHEN THEY REACH PARADICE SO THEY ALRE UFA AID
**I OF DET TH IF AM NO EA FREA ID BN CA AISE IV
**YO WT SHAT MR NEW
**
**EFIL WILL EB NA EASY E
**NONI ECIDARAP DEATH
* 03:18PM: I report my finding about the errors on line 15 (the 6th line of the 2nd section). Several errors are happening on the same line, suggestive of a systematic mistake.
* 03:23PM: Jarl reports his interpretation of the plaintext:
** SO THEY'RE ALL AFRAID OF DEATH I AM NOT AFRAID BECAUSE IT ...
* 04:19PM: I'm considering sending our partial solve to the FBI so they can help us work out the rest of it
* 05:47PM: Decided against reporting the solve early, to give our team more time to work it out. Developed a visualization of the errors on line 15 (6th line of the 2nd section).

=== Saturday, December 5th, 2020 ===
* 01:26AM: Jarl reports progress on the plaintext, resulting from a possible "skip" in the 2nd part. Jarl's latest plaintext:
** I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING
** TO CATCH ME THAT WASNT ME ON THE TV SHOW
** WHICH BRINGS UP A POINT ABOUT ME I AM NOT
** AFRAID OF THE GAS CHAMBER BECAUSE IT WILL
** SEND ME TO PARADICE (ALL THE)
**
** (SOO HEN) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO (THEYRE ALL) AFRAID
** OF DEATH I AM NOT AFRAID BECAUSE IT
** (YO WT SHAT MR NEW)
**
** EFIL WILL EB NA EASY ENO
** NI ECIDARAP DEATH
* 02:16AM: Jarl reports more detail on the skip in the 15th row, and the skip seems isolated to that row. But still some garble happening after that is fixed.
* 02:41AM: Jarl reports discovery that skipping cleartext "LIFEIS" in upper right section of the 2nd block fixes the remaining garbles. Plaintext now only has a few errors remaining.
* 02:50AM: Jarl reports full plaintext:
** I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING
** TO CATCH ME THAT WASNT ME ON THE TV SHOW
** WHICH BRINGS UP A POINT ABOUT ME I AM NOT
** AFRAID OF THE GAS CHAMBER BECAUSE IT WILL
** SEND ME TO PARADICE (ALL THE)
**
** (SOO HER) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO THEY ARE AFRAID
** OF DEATH I AM NOT AFRAID BECAUSE I KNOW THAT
** MY NEW LIFE IS
**
** EFIL WILL EB NA EASY ENO
** NI ECIDARAP DEATH
* 03:44AM: Jarl reports details on steps that were required to fix the 2nd section:
** Right-offset the RATENYRNOSRVSH fragment by 1 becoming HRATENYRNOSRVS. I think he skipped the H by mistake (during homophonic step) and then realized his error going into the 7th row and added the H back in at the end of the 6th row.
** Skip the positions of the "LIFEIS" fragment during untransposition.
** Now after transposition it will result in:
**
** (SOO HER) BECUASE E NOW HAVE ENOUGH SLAVES TO
** WORV FOR ME WHERE EVERYONE ELSE HUS NOTHING
** WHEN THEY REACH PARUDICE SO THEY ARE UFRAID OF
** DEATH I AM NOT AFRAID BECAASE I VNOW THAT MY NEW
**
** Fixing a few errors:
**
** (SOO HER) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
** DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
**
** Since the "LIFEIS" fragment was skipped it can be added in somewhere else, and I think it has to be at the end:
**
** (SOO HER) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
** DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW (LIFE IS)
* 07:56AM: I completed a PDF report of our solution and submitted it to my contacts at the FBI crypto lab.
* 08:02AM: First response from FBI crypto lab, unofficial confirmation
* 08:48AM: Second response, unofficial confirmation
* 08:49AM: Third response, further confirmation, phone call
Not sure about further timing on this day, but during the day the FBI took action on the solution, notifying others in the agency as well as working on a report of the solution to submit back to SFPD, the original requestor. Submission also planned to SF FBI.
=== Sunday, December 6th, 2020 ===
CRRU submitted the solution to FBI San Francisco in the evening.
Waiting for contact with FBI National Press Office to coordinate release of this news.

=== Monday, December 7th, 2020 ===
Talked to FBI National Press Office in the afternoon to discuss release plan. Allowing for all victim notifications to take place prior to releasing the news.
=== Thursday, December 10th 2020 ===
Talked to FBI National Press Office in the afternoon and was informed that final notifications will be completed by the end of the day and that the best time for the news release will be Friday.

[https://www.tapatalk.com/groups/zodiackillerfr/viewtopic.php?p=159817#p159817 Teased the pending release of the news.]

=== Friday, December 11th 2020 ===
* 06:00AM: [https://youtu.be/-1oQLPRE21o Explainer video (Let's Crack Zodiac Episode 5)] switched to Public. I posted the news on many social media outlets and forums, and emailed the LCZ mailing list.
** Post on [https://www.tapatalk.com/groups/zodiackillerfr/the-340-cipher-has-been-solved-t9434.html#p159875 Tom Voigt's forum]
** Post on [https://forum.zodiackillerciphers.com/community/news-wire/z340-has-been-solved/ Mike Morford's forum]
* 01:03PM: First news report by SF Chronicle, [https://twitter.com/KevinChron/status/1337458070570508289 announced by long time Zodiac reporter Kevin Fagan]
* 02:21PM: FBI San Francisco makes a public announcement of the solution [https://twitter.com/FBISanFrancisco/status/1337477701825925120 on their twitter account.]

Over the next several days, many news outlets reported on the solution.
[http://zodiackillerciphers.com/wiki/index.php?title=Compilation_of_news_reports_about_the_solution Click here for a compilation.]

Miscellaneous case updates and details

2024-07-25T14:23:21Z

Admin:

2024-07-26
* From Soze: Relating to the October 5, 1970 13 hole punch card that included “The pace isn’t any slower! In fact its just one big thirteenth”. The statement comes from a Smidgens cartoon strip by Robert Lee Cordray dated September 25, 1970. Here is a sampling that shows both Robert Cordray and Darlene Ferrin. [https://discord.com/channels/1260505612131897375/1263467644904800256/1263467646293118986 (source)]
2023-07-24
* [https://www.tapatalk.com/groups/zodiackillerfr/halloween-card-turns-up-in-the-wild-t10977.html Unmodified Halloween card turns up on eBay]
2022-08-14
* [https://www.tapatalk.com/groups/zodiackillerfr/nancy-bennallack-solved-8-10-22-zodiac-t10562-s190.html#p227338 Tom claims police are holding back three authentic Zodiac letters.]
** "Each has something to do with Sacramento. One is the DMV letter and another one or two has something to do with Nancy Bennallack."
2022-08-08
* From [https://discord.com/channels/996952324150931477/996952376894292018/1006054767388278814 Discord discussion] with Tom Voigt:
** Zodiac's Halloween card is postmarked only one day after the first news report of the death of [https://www.kcra.com/article/oldest-sacramento-county-cold-case-solved/40862241 Nancy Bennallack]
** Tom was asked not to mention "one of the items" related to Nancy and the Halloween card.
** "a foreign substance added to the card, plus a confirmed letter from Z apparently referring to nancy"
** "there are apparently three confirmed Zodiac letters not made public, and all have something to do with Sacramento"
** "DMV letter, Nancy letter, and I can't remember the third"
2022-08-05
* [https://www.tapatalk.com/groups/zodiackillerfr/the-2500-t10545.html#p225722 Partial list of cleared suspects], purported to be from an official report.
2022-07-14
* Mac suspect timeline
** [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s23460.html#p222860 Tom's version]
** [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s23470.html#p222881 chriscrozzz' version]
2022-07-12
* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s23180.html#p222346 Mac suspect timeline compared to Zodiac]
2022-07-02
* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s22570.html#p221094 Betty Lou Jensen's niece talks to Morf about Rainbow Girls and Masons]
** [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s22580.html#p221114 2nd post]
2022-06-02
* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s21240.html#p217551 Mystery profile sketch, from Morf]
2022-05-23
* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s20160.html#p215676 Detectives active on Zodiac case, per Tom Voigt]
** Detective Terry Schillinger is temporarily out with an injury at Vallejo PD so Detective Josh Caitham has the case for now.
** Dax West at the Solano County Sheriff's Department.
** Napa County has a cold case unit.
** Gianrico Pierucci was working the case in retirement for SFPD last I heard.
2022-05-21
* [https://www.tapatalk.com/groups/zodiackillerfr/reddit-youtube-zodiac-nonsense-t9369-s1560.html#p214627 Tom's summary of DNA evidence in Cheri Jo Bates case]
** A mitochondrial DNA profile was created based on what was found in Cheri's hand. No match has been found and I don't believe they are looking.
** More recently a nuclear DNA profile was created based on the blood found on her pants. The result? It was not foreign DNA.
** Nuclear DNA can't be compared to mitochondrial DNA.
2022-02-08
* [https://www.youtube.com/watch?v=2Y9RjRxzRRY&t=3606s Donald Harden calls during Tom Voigt et al.'s Crime Con in 2008]
2022-01-18
* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s11780.html#p194276 Montana/Colorado/Deer Lodge reporting timeline by mrseanz]
2022-01-13
* [https://www.tapatalk.com/groups/zodiackillerfr/zodiac-dna-update-dec-20th-2021-t10058-s880.html#p193924 Mike Morford claims there is DNA matching between a 1974 letter and 1969 letter, and that DNA was recovered from a 1978 letter.]
2022-01-11
* [https://www.tapatalk.com/groups/zodiackillerfr/donna-lass-not-a-zodiac-victim-t10062-s70.html#p193571 Letter from Donna Lass to her mother]
2022-01-10
* Mike Morford [https://zodiackiller.net/community/cecelia-shepard-bryan-hartnell-9-27-69/i-talked-to-another-lake-berryessa-witness-this-is-what-he-told-me/ talked to another Lake Berryessa witness]
* Transcription of [https://www.tapatalk.com/groups/zodiackillerfr/donna-lass-not-a-zodiac-victim-t10062-s60.html#p193475 Mary Pilker's report on Donna Lass]
** [https://www.tapatalk.com/groups/zodiackillerfr/donna-lass-not-a-zodiac-victim-t10062-s80.html#p193644 2nd report (not yet transcribed)]
2021-12-29
* Tom Voigt [https://www.tapatalk.com/groups/zodiackillerfr/discussion-chester-clark-klingel-aka-sam-from-eure-t10077.html#p191577 describes DNA ruling out the suspect Chester Clark Klingel]
2021-12-27
* [https://www.tapatalk.com/groups/zodiackillerfr/zodiac-killer-a-new-lead-for-2022-t10073.html Zodiac-like handwriting on old typewriter warranty card]
2021-12-26
* Rocky25's [https://www.tapatalk.com/groups/zodiackillerfr/zodiac-dna-update-dec-20th-2021-t10058-s620.html#p191250 list of suspects whose DNA samples have reportedly been compared to Zodiac's]
2021-12-22
* Tom Voigt [https://www.tapatalk.com/groups/zodiackillerfr/zodiac-dna-update-dec-20th-2021-t10058-s320.html#p190618 implies there is additional undisclosed (to the public) evidence included with Zodiac mailings]
* A BBC documentary [https://www.tapatalk.com/groups/zodiackillerfr/zodiac-dna-update-dec-20th-2021-t10058-s350.html#p190669 claimed a bullet was also included with Stine's bloody shirt]
2021-12-20
* Tom Voigt [https://www.tapatalk.com/groups/zodiackillerfr/dna-update-will-happen-dec-20th-2021-t10058-s40.html#p190267 discloses DNA-related information from unnamed sources.]
** The testing of Zodiac evidence produced a DNA profile. That's the good news. The bad news? The profile belonged to an individual who could not have been the Zodiac killer. That's as specific as I can be. One possibility is the profile belongs to an accomplice. Or an unknowing contributor not involved in the crimes. A major complication is during the Zodiac era, a popular form of civil disobedience was to reuse stamps. All of that is under consideration and the process is continuing.
** The original sample (2002) was of a male and still could belong to the actual Zodiac although it was not located where one would have preferred. [https://www.tapatalk.com/groups/zodiackillerfr/dna-update-will-happen-dec-20th-2021-t10058-s70.html#p190299 (Link)]
2021-12-01: Mike Morford received details from a Lake Berryessa witness. [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s10250.html#p187641 (link 1)] [https://www.tapatalk.com/groups/zodiackillerfr/one-of-the-sunbathing-girls-from-lake-b-chimes-in-t10024.html#p187644 (link 2)]
** Hi Mike, Yes I am THAT ******* a possible witness to the Lake Berryessa killer. I guess maybe some statute of limitations has expired because I've had a few people contact me. My identity and testimony at the time was under the agreement of secrecy as for years I was in fear of being identified and at risk. Obviously that criminal must be long dead by now. You didn't name the photo of the man you sent. And of course, 50 years on, I don't know. There are several photos I have been sent that look like the man I saw. Yes the photo you included very much looks like the man I saw, but your photo shows him quite heavy, and the man I saw was thin. A Frenchman has 'identified' the killer as Lawrence Kane, and the photo is similar to my identikit but I don't feel it's him. There is a 1950s photo of Arthur Leigh Allen, and that 50s photo is very strongly similar to who I saw. Photos of Gary Francis Poste show no resemblance. So there's no real answer I can provide. The man I saw stalked 3 of us girls and followed us to the lake. We sunbathed on the cove right next to where the killings took place, and left an hour or so before the attacks began. The man followed us to the shoreline and observed us from the trees. That's about all I can offer. Good luck with your research!
2012-06-06
* [http://zodiackillerciphers.com/images/prints-napa-sfpd.png Morf reporting what Napa investigators said when asked about comparing Napa prints to SFPD prints.]
2010-04-25
* JDean, reportedly a former VPD cop, on morf's old forum posted details about the children who witnessed the Stine murder. [https://zodiackiller.net/community/paul-stine-10-11-69/the-witnesses/#post-378 (link)] [http://zodiackillerciphers.com/jdean-witness-stories.txt (isolated post)]
2009
* Mike Morford says Ken Narlowe described to him the knife Hartnell saw: "weapon desc as a large knife, blade apprx 12 in long and 1 inch wide wooden handle with two brass rivets, could have been a bayonet. nothing further" [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s18450.html#p213212 (source)]

Halloween card

2024-07-15T13:50:49Z

Admin: /* Other symbology */

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Animals ===

==== Cattle Brands ====

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

==== Bird / Bat ====

The "Claude" AI gave this interpretation of the image: "This symbol appears to be a simple line drawing resembling a stylized bird or bat shape, with two angled lines forming what could be interpreted as wings, and two dots suggesting eyes."

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."
* [https://forum.zodiackillerciphers.com/community/postid/79587/ A reference to Z340's transposition scheme]

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]
* [https://www.tapatalk.com/groups/zodiackillerfr/wide-flange-beam-gaik-t2170.html "GAIK" in Brahmi alphabet]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]
* [https://en.wikipedia.org/wiki/Alchemical_symbol Alchemical symbols]
** Specifically, [https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Aqua_fortis.svg/48px-Aqua_fortis.svg.png the symbol for "Aqua fortis"]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Possible graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Catalog of sources for Zodiac's cipher symbols

2024-07-15T13:49:35Z

Admin: /* Astrology */

This is an attempt to track the various possible sources that people have discovered that resemble the symbols Zodiac used for his ciphers.

Note: The [[Halloween card]] has its own dedicated page.

= Alchemy =
* [https://en.wikipedia.org/wiki/Alchemical_symbol Alchemical symbols]

= Astrology =

* [https://en.wikipedia.org/wiki/Astrological_symbols Astrological symbols]
* [http://zodiackillerciphers.com/images/symbols/graysmith%20astrology.jpg Astrological symbols from Graysmith's book]
* [http://zodiackillerciphers.com/images/symbols/zodiac%20alphabet.jpg "Zodiac alphabet" from "Codes and Ciphers" by John Laffin]
* [https://en.wikipedia.org/wiki/Sun_cross Sun cross]

= Crypto toys for children =

* Secret code of Junior Justice Society of America: Decoder wheel [http://zodiackillerciphers.com/images/symbols/secret%20code%20of%20junior%20justice%20society%20of%20america%201.png (Front)] [http://zodiackillerciphers.com/images/symbols/secret%20code%20of%20junior%20justice%20society%20of%20america%202.png (Back)]
* [http://zodiackillerciphers.com/images/symbols/troopers%20secret%20code.png Troopers secret code]

= Cattle brands =

* [http://zodiackillerciphers.com/images/symbols/cowboy%20code%20cattle%20brands.png Cowboy code]

= Books =

* Alchemy: [http://zodiackillerciphers.com/images/symbols/alchemy%201.png Book excerpt 1] [http://zodiackillerciphers.com/images/symbols/alchemy%202.jpeg Book excerpt 2]
** Source: [https://www.alchemywebsite.com/symbols_barlet.html Alchemical Symbols from a work by Annibal Barlet]
* Arkon Daraul, "A History of Secret Societies"
** [http://zodiackillerciphers.com/images/daraul1.jpg Book cover]
** [http://zodiackillerciphers.com/images/daraul2.jpg Cipher system resembling Zodiac's symbols]
* David Kahn, "Codebreakers"
** [https://www.reddit.com/r/ZodiacKiller/comments/1da5ou9/z_crosshair_in_codebreakers/ Porta's cipher disk image from Kahn's book]

= Other languages and alphabets =

* Greek [http://zodiackillerciphers.com/images/greekalphabet1.jpg (Alphabet)] [http://www.zodiackiller.com/MyNameIs.html (Z13 comparison)]
* [https://en.wikipedia.org/wiki/Hobo#Hobo_signs_and_graffiti Hobo signs]
* [http://zodiackillerciphers.com/images/symbols/Hippie%20Code.png "Hippie" signs]
* [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]

= Teletype =

* [http://zodiackillerciphers.com/images/teletype-zodiac.jpg Teletype keyboard arrangement 1]
* [http://zodiackillerciphers.com/images/teletype-zodiac-2.jpg Teletype keyboard arrangement 2]

= Weather symbols =

* [http://zodiackillerciphers.com/images/weather-symbols.jpg Example 1]
* [http://zodiackillerciphers.com/images/weather-symbols-3.jpg Example 2]
* [http://zodiackillerciphers.com/images/weather-symbols-4.png Example 3]

= Maps =

* [https://pubs.usgs.gov/gip/TopographicMapSymbols/topomapsymbols.pdf Topographic map symbols]
** [https://www.tapatalk.com/groups/zodiackillerfr/the-zodiac-cipher-symbols-t9872.html Detailed thread]

= Misc =

* [https://www.tapatalk.com/groups/zodiackillerfr/reddit-youtube-zodiac-nonsense-and-facebook-too-t9369-s2020.html#p232347 Fast food wrapper]

Z13 Solutions

2024-07-07T21:51:17Z

Admin: /* From "Jasper" */

= Solutions that fit the ciphertext as is =

This section only shows proposed solutions that fit the cipher text "as is". No anagramming or other re-arrangements are used here, and the cipher is considered to be strictly a substitution cipher. Solutions that permit anagramming are very easy to come by, as there are several billion possible string combinations to choose from. Solutions that do not require anagramming are still numerous, however, which increases the difficulty of knowing which one is correct.

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=50&t=1390&p=24191#p24190 "Quill"] ==
* Eddie Penerden
* Stan T E Case (using "8"s as spaces)
* Greg N A Vega (using "8"s as spaces)

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5677 "glurk"] (homophonic solutions) ==
* Steve Pete West
* Adrian a Harrah
* Shannon E Nease
* Steve Pete Best
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Eddie Gene Oden
* Steve Pete Vest
* Barney E Yearby
* Gene Lyle Lange
* Eddie Gene Eden
* Ed Steven Eisen
* E Alva Vanallen
* Angelo Lyle Gay
* Eddie Rene Oden
* Isreal a Sarris
* Carl Bob Abarca
* Elliot O Roller
* Andre Reyes Day
* Ed Steve Nelsen
* Shane Pete East
* Lee Gene Levell
* Eddie Rene Eden
* Rueben E Segers
* Rueben E Severs
* Eddie Gene Aden
* Eddie Dewey Dew
* Shane Pete Mast
* Ed Steve Reeser
* Ed Steve Reiser
* Lee Rene Levell
* Neal Alan Amann
* Sean Lyle Lease
* Otto Alan Alton
* Otto Alan Acton
* Otto Alan Aston
* Otto Alan Anton
* Eddie Rene Aden
* Lee Jamal Abell
* Andre Gene Adan
* Reed Alan Ahern
* Shane Pete Fast
* Elliot O Yokley
* Elliot O Soules
* Lee Pete Levell
* Ira Lamar Adair
* Neil Lyle Laine
* Teodoro Tom Ott
* Otto Adam Altom
* Noah Alan Amann
* Eddy Alan Alden
* Lee Jewel Ezell
* Cory Bob Abarca
* Andre Rene Adan
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Earle Gene Wren
* Dean Rory Ready
* Dana Bob Obando
* Luis Rory Reily
* Otto Asa Santos
* Eric Asa Rapier
* Gino Lyle Lange
* Eddy Alan Arden
* Kent Lyle Linke
* Andre Dewey Daw
* Eddie Les Eades
* Louie Pete Ault
* Eddie Jewel Dew
* Ian Reyes Ennis
* Edison O Rosier
* Ollie Lee Enloe
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Ira Jamar Adair
* Earle Rene Wren
* Ernie Dewey New
* Lee Jewel Ewell
* Eddie Wes Eades
* Drew Rory Reedy
* Al Isaias Arias
* Ollie Derek Lor
* Cary Bob Abarca
* Emile Gene Lien
* Arlie Dewey Law
* Ollie Dewey Low
* Rob Dewey Embry
* Curt Bob Abarca
* Earl Asa Laurel
* Stefan Asa Hess
* Eddie Reyes Dey
* Eli Dana Rapier
* Dane Bob Obando
* Elmo Rory Ramey
* Lee Jere Levell
* Ali Rufus Urias
* Emile Rene Lien
* Eddie Jere Eder
* Stan Lyle Lease
* Chi Derek Edick
* Earle Gene Oren
* Emile Gene Bien
* Earle Gene Uren
* Arturo Rory Tao
* Otis Asa Nation
* Genaro Rory Ngo
* Dane Lyle Linde
* Dane Lyle Lynde
* Dane Lyle Lunde
* Scot Lyle Loose
* Ali Reyes Elias
* Art Solomon Tam
* Donn Bob Obando
* Dino Bob Obando
* Andre Jewel Daw
* Neal Adan Amann
* Emile Rene Bien
* Otto Adan Alton
* Earle Rene Uren
* Otto Adan Acton
* Earle Rene Oren
* Otto Adan Anton
* Otto Adan Aston
* Dallas Asa Olds
* Erik Asa Rapier
* Reed Adan Ahern
* Ernie Jewel New
* Donn Lyle Linde
* Dino Lyle Linde
* Donn Lyle Lynde
* Dino Lyle Lunde
* Donn Lyle Lunde
* Dino Lyle Lynde
* Dong Bob Obando
* Teodoro Tod Ott
* Stefan Asa Bess
* Noah Adan Amann
* Arlie Jewel Law
* Issac Jc Ocasio
* Arlie Reyes Lay
* Ed Teodoro Ater
* Ollie Jewel Low
* Eddy Adan Alden
* Shad Lyle Lease
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Shon Lyle Loose
* Dong Lyle Lunde
* Ollie Reyes Loy
* Stefan Asa Ness
* Earle Dewey Rew
* Reed Asa Sayers
* Anibal Asa Dias
* Noe Reyes Edens
* Delmar Asa Olds
* Isreal Al Abril
* Isreal Al April
* Earle Reyes Rey
* Ernie Les Eanes
* Eddy Adan Arden
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Ernie Reyes Ney
* Morgan Asa Arms
* Olin Asa Nation
* Lou Solomon Ulm
* Ernie Wes Eanes
* Ernie Rey Edney
* Odis Asa Nation
* Murray Asa Arms
* Noe Reyes Evens
* Ollie Dee Enloe
* Leif Rory Reily
* Elmo Asa Raymer
* Isaiah Asa Sais
* Anibal Asa Bias
* Ollie Jere Flor
* Reed Asa Sagers
* Reed Asa Sauers
* Stefan Asa Vess
* Stefan Asa Jess
* Stefan Asa Gess
* Ezra Asa Laurel
* Erin Asa Rapier
* Emile Jere Mier
* Emile Jere Pier
* Emile Jere Bier
* Earle Jewel Rew
* Emile Jere Wier
* Emile Jere Kier
* Anibal Asa Sias
* Isaias Asa Sais
* Paris Asa Serpa
* Arlie Jere Klar
* Luigi Gil Ifill
* Hai Solomon Ihm
* Darell L Ilardi
* Chi Derek Emick
* Eddie Lee Emdee
* Daryl Al Ilardi
* Arlie Rey Emlay
* Eddie Rene Iden
* Chi Derek Enick
* Earle Rene Hren
* Trevor O Howeth
* Earle Gene Hren
* Duncan Asa Ends
* Danial Asa Ends
* Louie Pete Hult
* Eddie Gene Iden
* Chas Asa Kasack
* Clay Asa Kasack
* Lee Jewel Euell
* Chad Asa Kasack
* Ian Dana Katnik
* Chet Asa Kazeck
* Shane Pete Kast
* Leo Jewel Etoll
* Ian Dana Kamnik
* M Keenan Ingemi
* M Vernon Ingemi
* Ernie Jere Iner
* Eddie Dee Emdee
* Isaias Asa Kais
* Ed Steven Elsen
* Steve Pete Jest
* Isaiah Asa Kais
* Theron O Howeth
* Neil Asa Garing
* Ernie Wes Ennes
* Noah Asa Galang
* Shane Leo Eraso
* Steve Pete Gest
* Emile Jere Gier
* Israel E Gehrig
* N Eugene Genung
* Neal Asa Galang
* Elijah Asa Fies
* Steve Pete Fest
* Eli Peter Etier
* Ed Steven Essen
* Stefan Asa Fess
* Chi Derek Erick
* Ollie Pete Flot
* Earle Pete Fret
* Ernie Ben Ennen
* Emile Jere Hier
* Ernie Len Ennen
* Ernie Ken Ennen
* Theron O Horeth
* Trevor O Horeth
* Lee Bo Holowell
* Chi Derek Evick
* Ernie Les Ennes
* Adrian Asa Gras
* Earle Gene Gren
* Noe Reyes Ewens
* Ollie Jere Glor
* Shad Asa Habash
* Stan Asa Habash
* Earle Rene Gren
* Sean Asa Habash
* Aldo Alan Ardan
* Andy Adan Ardan
* Art Jamal Antal
* Aldo Adan Ardan
* Eli Jamal Ariel
* Elijah Al Ariel
* Andy Alan Ardan
* Dorian Asa Ards
* Leland N Analla
* R Keenan Andera
* Lee Jamal Amell
* Ty Isaiah Amith
* L Vernon Angela
* Antwan Al Antal
* R Vernon Andera
* L Keenan Angela
* Ed Isaias Aries
* Art Jamal Attal
* Elmo Adan Aumen
* Shane Peter Ast
* Antwan Al Attal
* Otto Alan Auton
* Isreal Al Avril
* Elmo Alan Aumen
* Otto Adan Auton
* Elmo Alan Armen
* Norman Asa Arns
* Isreal Asa Aris
* Elmo Adan Armen
* Alva Adan Arvan
* Alva Alan Arvan
* Otto Adan Arton
* Otto Alan Arton
* Otto Adan Afton
* Otto Alan Afton
* Eddie Jere Ader
* Duane Reyes Ady
* Isaias Adam Aid
* Isaias Adan Aid
* Isaiah Adam Aid
* Isaiah Adan Aid
* Lyle Bob Abella
* Blake Peter Abt
* Ira Jamar Abair
* Ira Lamar Abair
* Chase Reyes Acy
* Lee Jamal Adell
* Tobias Asa Abts
* Derick C Acorda
* Otto Adan Aiton
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Aron Adan Aloan
* Aron Alan Aloan
* Amos Adan Aloan
* Amos Alan Aloan
* Arlie Gene Alan
* Arlie Rene Alan
* Otto Alan Aiton
* Nigel Al Alagna
* Cecil Al Alecca
* Al Isaias Alias
* Arlie Jere Alar
* Bradly L Aldaba
* Arlie Jewell Aw
* Emile Jere Dier
* Elijah Asa Dies
* Emile Gene Dien
* Emile Rene Dien
* Rey Reyes Eayrs
* Roy Reyes Eayrs
* Les Dewey Easly
* Ray Reyes Eayrs
* Earl E Deserres
* Eddie Derek Der
* Earle Deserres
* Stefan Asa Dess
* Steve Pete Dest
* Ezra E Deserres
* Shelby Bob Deso
* Royce Les Eayrs
* Eddie Ben Elden
* Eddie Ken Elden
* Eddie Ken Eiden
* Eddie Len Eiden
* Chi Derek Elick
* Lee Solomon Elm
* Eddie Len Elden
* Ali Keven Elian
* Lee Jewel Edell
* Arlie Leo Edlao
* Royce Wes Eayrs
* Ed Steven Ebsen
* Al Steven Ehsan
* Eddie Ben Eiden
* Reuben Ed Efurd
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* Earle Rene Bren
* Robert Rory Bro
* L Rocco Cachola
* L Royce Cachola
* Royce Rene Byrn
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Otto Adan Axton
* Otto Alan Axton
* Adrian Asa Bras
* Earle Gene Bren
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Leo Gene Debold
* Leo Jere Debold
* Isaias Asa Dais
* Andre Derek Dar
* Leonel E Debold
* Lionel E Debold
* Leo Pete Debold
* Leo Rene Debold
* N Royce Cicconi
* Arlie Gene Clan
* N Boyce Cicconi
* N Rocco Cicconi
* Bruce Jere Cubr
* Isaiah Asa Dais
* Arlie Rene Clan
* Arlie Jere Clar
* Cleo Asa Kazeck
* Dean Rory Roady
* Ryan Rory Roary
* Ed Luigi Riller
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elwood O Rohwer
* Elmo Rory Romey
* Ed Luigi Rigler
* Deon Rory Rhody
* Dion Rory Rhody
* Eli Rene Revier
* Eliseo E Revier
* Ed Luigi Ridler
* Drew Rory Riedy
* Doug Rory Rhudy
* Anibal Asa Rias
* Dino Rory Rondy
* Ivan Asa Salais
* Silas Asa Salsa
* Isaiah a Salais
* Isaias a Salais
* Thomas a Sanots
* Troy Asa Sanots
* Alva Asa Salvas
* Denis Asa Sanda
* Ira Dana Salais
* Cesar Ira Rosca
* Drew Rory Ruedy
* Dong Rory Rondy
* Donn Rory Rondy
* Neil Asa Sabins
* Eloy Asa Sagoes
* Truman Asa Ruts
* Emery Ty Ryneer
* Eli Gene Regier
* Eli Jere Regier
* Ryan Rory Reary
* Ed Steve Reaser
* Eliseo E Regier
* Elmo Rory Remey
* Eli Pete Regier
* Eli Rene Regier
* Ezra Rory Rarey
* Dana Rory Randy
* Dane Rory Randy
* Art Dana Rajtar
* Elmo Asa Rammer
* Donn Rory Randy
* Earl Rory Rarey
* Dino Rory Randy
* Dong Rory Randy
* Eli Gene Renier
* Eddy E Resendes
* Stefan Asa Ress
* Ed Dee Resendes
* Eli Jere Revier
* Eli Pete Revier
* Alva Rory Revay
* Eli Gene Revier
* Eddie Resendes
* Eli Rene Renier
* Eliseo E Renier
* Eli Jere Renier
* Eli Pete Renier
* Art Pete Rentar
* Art Rene Rentar
* Art Gene Rentar
* Art Jere Rentar
* Alva Asa Sarvas
* Emmitt Ty Tomey
* Emmett Ty Tumey
* Emile Pete Tiet
* Emmett Ty Tomey
* Isaiah Asa Vais
* Isaias Asa Vais
* Emmitt Ty Tumey
* Benito Ty Tunby
* Emile Jere Tier
* T Dusty Tatsuta
* T Rusty Tatsuta
* Noe Dana Talent
* Noel Asa Talent
* Emile Gene Tien
* Emile Rene Tien
* Stefan Asa Tess
* Steve Pete Test
* E Otha Vanasten
* Elijah Asa Wies
* Isaiah Asa Zais
* Emile Gene Wien
* Emile Rene Wien
* Emile Rene Zien
* Emile Jere Zier
* Isaias Asa Zais
* Emile Gene Zien
* Stefan Asa Wess
* Emile Rene Vien
* Emile Jere Vier
* Anibal Asa Vias
* Emile Gene Vien
* N Mike Wedekind
* Neil E Wedekind
* Isaiah Asa Wais
* Isaias Asa Wais
* Ali Gene Setias
* Ali Jere Setias
* Noe Rene Serens
* Moses Asa Sesma
* Louis Asa Shula
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Noe Pete Serens
* Ezra Asa Sayres
* Rueben E Sebers
* Reed Asa Savers
* Earl Asa Sayres
* Noe Gene Serens
* Noe Jere Serens
* Miles Asa Selma
* Myles Asa Selma
* Emile Gene Sien
* Thad Asa Tabatt
* Tuan Asa Tabatt
* Ed Teodoro Ster
* Louie Pete Sult
* Duane Pete Tadt
* Graham Asa Tags
* Leo Dana Tabolt
* Leon Asa Tabolt
* Antwan Asa Stas
* Al Luigi Sillas
* Ed Luigi Sirles
* Emile Rene Sien
* Emile Jere Sier
* Louis Asa Soula
* Al Teodoro Star
* Ollie Pete Slot
* Edison O Solies
* Shelby Bob Leso
* Stefan Asa Less
* Tony Lyle Lente
* Zane Lyle Lenze
* Bret Lyle Liebe
* Elijah Asa Lies
* Anibal Asa Lias
* Robt Lyle Libre
* King Lyle Lenke
* Lee Dana Layell
* Eddy Lyle Ledee
* Arlie Keven Lav
* Lee Dana Lavell
* Lyle Lyle Lelle
* Kent Lyle Lenke
* Theo Lyle Leete
* Trey Lyle Leete
* Gene Lyle Longe
* Gino Lyle Lynge
* Isaiah Asa Mais
* Cecil Eli Lucci
* Gene Lyle Lynge
* I Otha Masaitis
* C Mike Mehelich
* Isaias Asa Mais
* Eddy a Marander
* Cecil Ali Lucci
* Daryl Eli Lordi
* Earl Lyle Loree
* Gino Lyle Longe
* Daryl Ali Lordi
* Ollie Peter Lot
* Paul Lyle Loupe
* Ezra Lyle Loree
* Gary Lyle Lorge
* Alvaro R Krivak
* Cletus U Kubeck
* W Rocky Knknown
* Adrian Asa Kras
* Duane Pete Ladt
* Isaiah Asa Lais
* Robt Lyle Labre
* Lee Dana Ladell
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Keenan Asa Keks
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Stefan Asa Kess
* Isaias Asa Lais
* Kurt Lyle Larke
* Vern Lyle Larve
* Kirk Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Lee Dana Lasell
* Shane Pete Last
* Karl Lyle Larke
* Dane Lyle Lande
* Dino Lyle Lande
* Elmo Asa Lammel
* Dana Lyle Lande
* Zane Lyle Lanze
* Dirk Lyle Larde
* Dong Lyle Lande
* Donn Lyle Lande
* Stefan Asa Mess
* Genaro R Orengo
* Isreal Asa Oris
* Otto Everett or
* Adrian Asa Oras
* Al Teodoro Otar
* Santo Coy Ounsy
* Morgan Asa Orms
* Murray Asa Orms
* Teodoro O Omoto
* Steve Pete Oest
* Emile Gene Oien
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Leo Solomon Olm
* Emile Rene Oien
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raemer
* Eddy Asa Raider
* Eddy Asa Radder
* Eddy Asa Raeder
* Isaias Asa Rais
* Antwan a Rajtar
* Elmo Asa Raimer
* Isaiah Asa Rais
* Adrian Adan Rad
* Isaias Asa Pais
* Elijah Asa Pies
* Ollie Jewell Ow
* Isaiah Asa Pais
* Rupert Rory Pro
* Adrian Adam Rad
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Isaias a Narain
* Ivan Asa Narain
* Steve Pete Nest
* Ernie Peter Net
* Ed Steve Neisen
* Ed Steve Nessen
* Isaiah a Narain
* Shannon Z Naasz
* Odis Asa Nacion
* Anibal Asa Mias
* Al Luigi Millam
* Otto Asa Nanton
* Ira Dana Narain
* Olin Asa Nacion
* Otis Asa Nacion
* Ernie Keven Nev
* L Damon Odonald
* L Daron Odonald
* L Aaron Odonald
* L Carol Odonald
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* L Jarod Odonald
* Eddie Jere Oder
* Austin I Nissan
* Elliot O Nowlen
* Emile Jere Nier
* Ian Solomon Nim
* Neal Bob Obiano
* Noah Bob Obiano
* Elroy Ty Nygren
* Emery Ty Nyreen
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5733 "glurk"] (non-homophonic solutions) ==
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Angelo Lyle Gay
* Andre Reyes Day
* Shane Pete Mast
* Shane Pete Fast
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Dean Rory Ready
* Luis Rory Reily
* Gino Lyle Lange
* Louie Pete Ault
* Edison O Rosier
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Arlie Dewey Law
* Rob Dewey Embry
* Eli Dana Rapier
* Elmo Rory Ramey
* Ali Rufus Urias
* Chi Derek Edick
* Otis Asa Nation
* Ali Reyes Elias
* Art Solomon Tam
* Andre Jewel Daw
* Dino Lyle Linde
* Dino Lyle Lunde
* Dino Lyle Lynde
* Arlie Reyes Lay
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Dong Lyle Lunde
* Delmar Asa Olds
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Odis Asa Nation
* Leif Rory Reily
* Elmo Asa Raymer
* Hai Solomon Ihm
* Chi Derek Emick
* Daryl Al Ilardi
* Arlie Rey Emlay
* Chi Derek Enick
* Trevor O Howeth
* Louie Pete Hult
* Chet Asa Kazeck
* Shane Pete Kast
* M Vernon Ingemi
* Neil Asa Garing
* Shane Leo Eraso
* Israel E Gehrig
* Elijah Asa Fies
* Chi Derek Erick
* Trevor O Horeth
* Chi Derek Evick
* L Vernon Angela
* Elmo Adan Aumen
* Shane Peter Ast
* Elmo Alan Aumen
* Elmo Alan Armen
* Elmo Adan Armen
* Duane Reyes Ady
* Blake Peter Abt
* Chase Reyes Acy
* Derick C Acorda
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Elijah Asa Dies
* Shelby Bob Deso
* Royce Les Eayrs
* Chi Derek Elick
* Ali Keven Elian
* Royce Wes Eayrs
* Al Steven Ehsan
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* L Royce Cachola
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Arlie Gene Clan
* Arlie Rene Clan
* Cleo Asa Kazeck
* Dean Rory Roady
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elmo Rory Romey
* Ed Luigi Rigler
* Ed Luigi Ridler
* Doug Rory Rhudy
* Dino Rory Rondy
* Dong Rory Rondy
* Truman Asa Ruts
* Dana Rory Randy
* Dane Rory Randy
* Dino Rory Randy
* Dong Rory Randy
* Benito Ty Tunby
* Noel Asa Talent
* E Otha Vanasten
* Elijah Asa Wies
* N Mike Wedekind
* Ali Gene Setias
* Ali Jere Setias
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Louie Pete Sult
* Leo Dana Tabolt
* Leon Asa Tabolt
* Ed Luigi Sirles
* Al Teodoro Star
* Shelby Bob Leso
* Elijah Asa Lies
* Robt Lyle Libre
* Arlie Keven Lav
* Gino Lyle Lynge
* C Mike Mehelich
* Daryl Eli Lordi
* Gino Lyle Longe
* Daryl Ali Lordi
* Gary Lyle Lorge
* Cletus U Kubeck
* Duane Pete Ladt
* Robt Lyle Labre
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Kurt Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Shane Pete Last
* Dino Lyle Lande
* Dana Lyle Lande
* Dirk Lyle Larde
* Dong Lyle Lande
* Santo Coy Ounsy
* Morgan Asa Orms
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raimer
* Elijah Asa Pies
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Odis Asa Nacion
* Otis Asa Nacion
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* Elroy Ty Nygren
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5676 "PBFred"] ==
* Evil Anal Aziel
== From doranchak [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=30#p22403 (1)] [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=40#p22438 (2)]==
* A McNamara Scar
* Ate severed ear
* Trove Behemoth
* Spiro Motorist
* Laura Catapult
* Alice Venetian
* Agile Venetian
* Lebanon Enable
* Indiana Saudis
* Extras Adopted
* Athlete Lethal
* Achieve Lethal
* a Fine Venetian
* of Flanagan Fog
* to One Behemoth
* Extras Adapted
* Training Neat
* Chinese Eel Ice
* Artists Use Tau
* Our Bananas Ron
* Its Revered Sir
* Our Faraway Row
* Old Bikinis Don
* Of These Men Tom (or Of The Semen Tom)
* Greats To The Go
* Or I Was A Nation
* O He Was A Face Of
* [http://www.zodiackillerciphers.com/?p=152 Over 2,700 phrases from Project Gutenberg experiment]
* [https://docs.google.com/spreadsheets/d/13R16xILq6XIWTklErwZq7ltod7EG08-zeiG0AnAtsl4/edit?usp=sharing Another Project Gutenberg experiment, scanned 61.5 GB of text]
* [http://www.zodiackillerciphers.com/?p=467 From article], person names:
** Chastity Tracy
** Erica Natalie T
** Islami M Amelia
** Eddie Resendes
** Ernie Zerenner
** Aileen Enerlan
** Chitumu Eunice
** Ariyana Mariam
** Sripada Harish
** Ali Raja Mariam
** Arriaga Laura L
** Duitama David D
** Steve Menezes N
** Arriaza Laura L
** Arizala Maria M
** Adriana Laura L
** Aziz a Zahaniah
* [http://www.zodiackillerciphers.com/?p=467 From article], phrases / word combinations:
** Sarah The Horse
** Uncle Peter Cut
** Achieve Lethal
** Obscene Nelson
** Extreme Reuter
** Emperors Ropes
** Leigh The Haile
** Kane Pops Punks
** Gareth Tot Ergo
** Niece Gene Penn
** Drop Rarer Code
** Door Non-Encode
** Iraq Alan Again
** All Banana Alan
** Alice Venetian
** Laura Catapult
** Afghan Amalgam
** Reassess Scars
** Clara Cataract
** Shannon Encase
** Okinawa Nation
** Indiana Saudis
** Regan Adalard
** Drippy Peptide
** Outlet Erector
** Akira Canadian
** Adriana Marram
** Mary Nina Norma
** Robert Rory Bro
** Smile Pete List
** Mary Tate Terme
** Mary Gags Germs
** Ryan Amaya Gary
** Daniel Eye Andy
** Eats Bobs Bates
** Kill Baby Bulky
** Shit Pipe Poise
** Eric Alan Alien
** Slave Pete Last
** Extra War After
** Murder Eye Army
** Clara Fatal Act
** Encoded Odd CEO
** [http://zodiackillerciphers.com/z13wordsearch-results-2-sorted.txt List of 283 phrases / word combinations that use two words]
** [http://zodiackillerciphers.com/z13wordsearch-results-3-sorted.txt List of 1,283,443 phrases / word combinations that use three words]
* From another corpus test for [https://www.reddit.com/r/ZodiacKiller/comments/axqx4z/z13_my_name_is_cipher/ reddit post]:
** Chief of Africa
** Uncle Peter Cut
** of Hair It Is Hot
** of These Newton
** at Me O Son of Man
** a Wide Venetian
** a Ripe Venetian
** Avis, a Canadian
** India. Was, and Is.
** I Saw Alan Again
** I Was a Man Again
** I Had a Man Again
** Near a Way As Any
** Claus Asks Jack
** Guest at Otsego
** One Has a Name on
** One Had an Axe on
** As if a Canadian
** Oh No It It Is Not
** Is That As Art Is
** Nearer Eden and
** Niagara Day And
** [http://zodiackillerciphers.com/z13-corpus-solutions.txt Full unprocessed results]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4305&p=69616 More results from corpus scanning:]
** So I'm a Satanist
** So I'm a Fatalist (from glurk)
** A Dog, a Cat, a Goat
** or Steve Nelson
** As I Had an Asian
** a Kid: a Canadian
** Emperor's Ropes
** As Real As Auras
** That I Die, I Hate
** One Has a Name on
** I've Had an Axe in
** Spectate These
** if I Was a Nazi in
** I Eat a Banana in
** As I'm a Canadian
** I Was a Canadian
** Leave Helen All
** Edit As an Alien
** Shakalaka Mask
** Shit! a Natalist!
** Shit! a Fatalist!
** Shit! a Satanist!
** Is a Pagan Again
** Extra Caracter
** and Gamal Abdal
** Donut. It Stands.
** Al Is a Canadian
** Reign on Entire
** I've Had a Dane I.D.
** Least It Steals
** Ratio, Do You Try?
** Said As a Taoist

== From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6406 "Deryk"] ==
* Male, Initial: M.T.
== From [https://www.tapatalk.com/groups/zodiackillerfr/my-name-is-zodiac-t2276-s20.html#p139086 "MickCal"] ==
* OL STEVE NELSON
== From [https://discord.com/channels/996952324150931477/996952376894292018/1135335122527342604 "Toad"] ==
* AMIGO COLONIAL
== From [https://discord.com/channels/996952324150931477/996952376894292018/1033254655381217320 "Antisquid42"] ==
* John E. Heresh Jr.
* Donald LeLinde
* Neal O’Donovann
* Doug Lyle Laude
* Chip O. Kozowicz
* Seth Everett Sr.
* Andrew E. Levdal
* Paul Lyle Loupe
* Shiloh Oto List
* Juan O. Corona Jr.
* Frank X. LeLoafe
* Leo Solomon Olm
== From [http://zodiackillerciphers.com/z13_2_word_solutions.txt "rando"] ==
* [http://zodiackillerciphers.com/z13_2_word_solutions.txt 3,142 2-word solutions]

== Partial solution from [http://zodiackiller.21.forumer.com/viewtopic.php?p=119889#119889 "granny101"] ==
* ILLNEVETELLIT ("I'LL NEVER TELL IT", with the "R" missing)
== From [https://www.tapatalk.com/groups/zodiackillerfr/solution-to-the-challenge-t11196.html#p264079 "CipherS0luti0ns"] ==
* SOLVE REVEALS V
== From [https://discord.com/channels/996952324150931477/996952376894292018/1259617636715860028 "Jasper"] ==
* HOPE IT IS IN PHS (PHS assumed to be reference to Presidio Heights, or Presidio Hill School)

= Solutions that fit if you first reverse the cipher =

TODO

= Solutions that fit the ciphertext if you permit anagramming =

Rearranging the cipher text significantly reduces the constraints on possible solutions. As [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=20#p13716 "glurk"] points out, anagramming the 13 symbols permits a very large variety of possible solutions, which makes it nearly impossible to validate any given solution derived this way.

Here are some examples of solutions that arise from anagramming:

* [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=40#p13807 Small sampling from "sincos"]
* From doranchak:
** 13-letter English words that have the same letter distribution as the symbols of the cipher:
*** international, participation, concentration, interventions, investigating, participating, inappropriate, investigative, authoritarian, mediterranean, intentionally, accommodation, strengthening, commissioners, differentiate, collaborators, incorporation, unwillingness, mismanagement, superstitious, mathematician, nationalities, instantaneous, nationalistic, inconsistency, choreographer, preponderance, condescending, applicability, contingencies, indeterminate, sarcastically, temperamental, disillusioned, prerequisites, intelligences, irreplaceable, headquartered, reincarnation, proportionate, appropriating, inclusiveness, preservatives, ornamentation, uninteresting, incapacitated, contaminating, irrationality, abolitionists, improprieties, structuralist, sharecroppers, solicitations, intermarriage, arbitrariness, impermissible, disconnection, professorship, scintillating, insufficiency, spectroscopic, satisfactions
** Small sampling of 13-letter surnames that have the same letter distribution as the symbols of the cipher:
*** radhakrishnan, bhattacharjee, villavicencio, chattopadhyay, oluwatobiloba, degraffenreid, knappenberger, brandenburger, hebblethwaite, rathakrishnan, degraffenried, sahasrabuddhe, stamatopoulos, schlegelmilch, sastrowardoyo, konstantinova, muruganantham, thorsteinsson, madhusoodanan, wojciechowicz, hintermeister, klingenberger, vansteenkiste, raveendranath, blankenbiller, messerschmitt, abdollahzadeh, vlaisavljevic, stamatopoulou, giacomantonio, gebregziabher, gardarsdottir, blattenberger, agustiningsih, sverrisdottir, shirmohammadi, reichenbacher, schottenstein, christophoros, javakhishvili, sundareswaran, schiermeister, kaluhiokalani, natsvlishvili, monteferrante, ntakirutimana, derakhshandeh, winternheimer, spangenberger, liechtenstein, heiderscheidt, chandrarathne, shettlesworth
** [http://zodiackillerciphers.com/all-names-z13-list2-sorted.txt A sampling of 69,607 common first-last name combinations] that have the same letter distribution as the symbols of the cipher.
*** [http://zodiackillersite.com/viewtopic.php?p=18552#p18552 (Original broken forum link)]
* From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6376 Tom Voigt]:
** knickerbocker
** [http://zodiackiller.21.forumer.com/viewtopic.php?p=120299#120299 aintgonnatell]
* From [http://www.santarosahitchhikermurders.com/ Deb Silva]:
** [http://en.wikipedia.org/wiki/Bobby_Beausoleil Bob Beausoleil]
* From Anonymous:
** Jimmy Phillips (also credited to [http://zodiackiller.fr.yuku.com/topic/3827/Jimmy-Phillips alanbenjy])
* From Christer Böke:
** Frank Frazetta ([http://zodiackillersite.com/viewtopic.php?f=63&t=1275 Tim Holt] was drawn by Frank Bollle and Frank Frazetta)
** Grant Santiago
* From [https://www.tapatalk.com/groups/zodiackillerfr/simple-solve-for-the-my-name-is-t8738.html#p145360 jaydeezodiachunter]:
** Debbie Faraday

= Solutions that fit if you relax other constraints of the cipher =

Solutions that fit if you allow all three "circled 8" symbols to be wildcards:
* From Michael Kelleher:
** thebigsecrete
Solutions that are produced via multiple operations:
* From [http://www.zodiackillerciphers.com/?p=46 Lyndon Lafferty]:
** NAME GRANT, or NAME IS GRANT
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/detailed-solution-to-z13-and-z32/ Faycal Ziraoui's solution]
A solution that applies the 408 key and interprets some symbols as nulls:
* from [http://zodiackiller.fr.yuku.com/topic/6839/Zodiacs-Name-using-408-Key Rembrandt]:
** ED SHAW
Solutions with one name part in the middle, and another name part split in half and written backwards:
* [http://www.zodiackillersite.com/viewtopic.php?p=69126#p69126 DEBBIE FARADAY]

= Other interpretations =

* "My name is" contains 8 letters. The cipher text contains 8 letters and 5 special symbols. The special symbols contain Zodiac's name and the rest just mean "My name is" (Source: Jeppesen)
* [https://www.tapatalk.com/groups/zodiackillerfr/general-book-discussion-for-hunted-the-zodiac-murd-t10141.html#p197345 "Set addition" interpretation of Z13 by Doug Oswell], resulting in solution: "FROM TED KACZYNS[K]I"
* [https://www.tapatalk.com/groups/zodiackillerfr/paul-astrup-s-theory-meteorological-symbols-challe-t10261.html#p202558 Weather symbols]
* The line after "My name is" is roughly above symbols that resemble "Tom" spelled backwards. (Source: David Cauley via YouTube comments)

Z13 Solutions

2024-07-07T21:50:50Z

Admin: /* From "Jasper" */

= Solutions that fit the ciphertext as is =

This section only shows proposed solutions that fit the cipher text "as is". No anagramming or other re-arrangements are used here, and the cipher is considered to be strictly a substitution cipher. Solutions that permit anagramming are very easy to come by, as there are several billion possible string combinations to choose from. Solutions that do not require anagramming are still numerous, however, which increases the difficulty of knowing which one is correct.

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=50&t=1390&p=24191#p24190 "Quill"] ==
* Eddie Penerden
* Stan T E Case (using "8"s as spaces)
* Greg N A Vega (using "8"s as spaces)

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5677 "glurk"] (homophonic solutions) ==
* Steve Pete West
* Adrian a Harrah
* Shannon E Nease
* Steve Pete Best
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Eddie Gene Oden
* Steve Pete Vest
* Barney E Yearby
* Gene Lyle Lange
* Eddie Gene Eden
* Ed Steven Eisen
* E Alva Vanallen
* Angelo Lyle Gay
* Eddie Rene Oden
* Isreal a Sarris
* Carl Bob Abarca
* Elliot O Roller
* Andre Reyes Day
* Ed Steve Nelsen
* Shane Pete East
* Lee Gene Levell
* Eddie Rene Eden
* Rueben E Segers
* Rueben E Severs
* Eddie Gene Aden
* Eddie Dewey Dew
* Shane Pete Mast
* Ed Steve Reeser
* Ed Steve Reiser
* Lee Rene Levell
* Neal Alan Amann
* Sean Lyle Lease
* Otto Alan Alton
* Otto Alan Acton
* Otto Alan Aston
* Otto Alan Anton
* Eddie Rene Aden
* Lee Jamal Abell
* Andre Gene Adan
* Reed Alan Ahern
* Shane Pete Fast
* Elliot O Yokley
* Elliot O Soules
* Lee Pete Levell
* Ira Lamar Adair
* Neil Lyle Laine
* Teodoro Tom Ott
* Otto Adam Altom
* Noah Alan Amann
* Eddy Alan Alden
* Lee Jewel Ezell
* Cory Bob Abarca
* Andre Rene Adan
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Earle Gene Wren
* Dean Rory Ready
* Dana Bob Obando
* Luis Rory Reily
* Otto Asa Santos
* Eric Asa Rapier
* Gino Lyle Lange
* Eddy Alan Arden
* Kent Lyle Linke
* Andre Dewey Daw
* Eddie Les Eades
* Louie Pete Ault
* Eddie Jewel Dew
* Ian Reyes Ennis
* Edison O Rosier
* Ollie Lee Enloe
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Ira Jamar Adair
* Earle Rene Wren
* Ernie Dewey New
* Lee Jewel Ewell
* Eddie Wes Eades
* Drew Rory Reedy
* Al Isaias Arias
* Ollie Derek Lor
* Cary Bob Abarca
* Emile Gene Lien
* Arlie Dewey Law
* Ollie Dewey Low
* Rob Dewey Embry
* Curt Bob Abarca
* Earl Asa Laurel
* Stefan Asa Hess
* Eddie Reyes Dey
* Eli Dana Rapier
* Dane Bob Obando
* Elmo Rory Ramey
* Lee Jere Levell
* Ali Rufus Urias
* Emile Rene Lien
* Eddie Jere Eder
* Stan Lyle Lease
* Chi Derek Edick
* Earle Gene Oren
* Emile Gene Bien
* Earle Gene Uren
* Arturo Rory Tao
* Otis Asa Nation
* Genaro Rory Ngo
* Dane Lyle Linde
* Dane Lyle Lynde
* Dane Lyle Lunde
* Scot Lyle Loose
* Ali Reyes Elias
* Art Solomon Tam
* Donn Bob Obando
* Dino Bob Obando
* Andre Jewel Daw
* Neal Adan Amann
* Emile Rene Bien
* Otto Adan Alton
* Earle Rene Uren
* Otto Adan Acton
* Earle Rene Oren
* Otto Adan Anton
* Otto Adan Aston
* Dallas Asa Olds
* Erik Asa Rapier
* Reed Adan Ahern
* Ernie Jewel New
* Donn Lyle Linde
* Dino Lyle Linde
* Donn Lyle Lynde
* Dino Lyle Lunde
* Donn Lyle Lunde
* Dino Lyle Lynde
* Dong Bob Obando
* Teodoro Tod Ott
* Stefan Asa Bess
* Noah Adan Amann
* Arlie Jewel Law
* Issac Jc Ocasio
* Arlie Reyes Lay
* Ed Teodoro Ater
* Ollie Jewel Low
* Eddy Adan Alden
* Shad Lyle Lease
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Shon Lyle Loose
* Dong Lyle Lunde
* Ollie Reyes Loy
* Stefan Asa Ness
* Earle Dewey Rew
* Reed Asa Sayers
* Anibal Asa Dias
* Noe Reyes Edens
* Delmar Asa Olds
* Isreal Al Abril
* Isreal Al April
* Earle Reyes Rey
* Ernie Les Eanes
* Eddy Adan Arden
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Ernie Reyes Ney
* Morgan Asa Arms
* Olin Asa Nation
* Lou Solomon Ulm
* Ernie Wes Eanes
* Ernie Rey Edney
* Odis Asa Nation
* Murray Asa Arms
* Noe Reyes Evens
* Ollie Dee Enloe
* Leif Rory Reily
* Elmo Asa Raymer
* Isaiah Asa Sais
* Anibal Asa Bias
* Ollie Jere Flor
* Reed Asa Sagers
* Reed Asa Sauers
* Stefan Asa Vess
* Stefan Asa Jess
* Stefan Asa Gess
* Ezra Asa Laurel
* Erin Asa Rapier
* Emile Jere Mier
* Emile Jere Pier
* Emile Jere Bier
* Earle Jewel Rew
* Emile Jere Wier
* Emile Jere Kier
* Anibal Asa Sias
* Isaias Asa Sais
* Paris Asa Serpa
* Arlie Jere Klar
* Luigi Gil Ifill
* Hai Solomon Ihm
* Darell L Ilardi
* Chi Derek Emick
* Eddie Lee Emdee
* Daryl Al Ilardi
* Arlie Rey Emlay
* Eddie Rene Iden
* Chi Derek Enick
* Earle Rene Hren
* Trevor O Howeth
* Earle Gene Hren
* Duncan Asa Ends
* Danial Asa Ends
* Louie Pete Hult
* Eddie Gene Iden
* Chas Asa Kasack
* Clay Asa Kasack
* Lee Jewel Euell
* Chad Asa Kasack
* Ian Dana Katnik
* Chet Asa Kazeck
* Shane Pete Kast
* Leo Jewel Etoll
* Ian Dana Kamnik
* M Keenan Ingemi
* M Vernon Ingemi
* Ernie Jere Iner
* Eddie Dee Emdee
* Isaias Asa Kais
* Ed Steven Elsen
* Steve Pete Jest
* Isaiah Asa Kais
* Theron O Howeth
* Neil Asa Garing
* Ernie Wes Ennes
* Noah Asa Galang
* Shane Leo Eraso
* Steve Pete Gest
* Emile Jere Gier
* Israel E Gehrig
* N Eugene Genung
* Neal Asa Galang
* Elijah Asa Fies
* Steve Pete Fest
* Eli Peter Etier
* Ed Steven Essen
* Stefan Asa Fess
* Chi Derek Erick
* Ollie Pete Flot
* Earle Pete Fret
* Ernie Ben Ennen
* Emile Jere Hier
* Ernie Len Ennen
* Ernie Ken Ennen
* Theron O Horeth
* Trevor O Horeth
* Lee Bo Holowell
* Chi Derek Evick
* Ernie Les Ennes
* Adrian Asa Gras
* Earle Gene Gren
* Noe Reyes Ewens
* Ollie Jere Glor
* Shad Asa Habash
* Stan Asa Habash
* Earle Rene Gren
* Sean Asa Habash
* Aldo Alan Ardan
* Andy Adan Ardan
* Art Jamal Antal
* Aldo Adan Ardan
* Eli Jamal Ariel
* Elijah Al Ariel
* Andy Alan Ardan
* Dorian Asa Ards
* Leland N Analla
* R Keenan Andera
* Lee Jamal Amell
* Ty Isaiah Amith
* L Vernon Angela
* Antwan Al Antal
* R Vernon Andera
* L Keenan Angela
* Ed Isaias Aries
* Art Jamal Attal
* Elmo Adan Aumen
* Shane Peter Ast
* Antwan Al Attal
* Otto Alan Auton
* Isreal Al Avril
* Elmo Alan Aumen
* Otto Adan Auton
* Elmo Alan Armen
* Norman Asa Arns
* Isreal Asa Aris
* Elmo Adan Armen
* Alva Adan Arvan
* Alva Alan Arvan
* Otto Adan Arton
* Otto Alan Arton
* Otto Adan Afton
* Otto Alan Afton
* Eddie Jere Ader
* Duane Reyes Ady
* Isaias Adam Aid
* Isaias Adan Aid
* Isaiah Adam Aid
* Isaiah Adan Aid
* Lyle Bob Abella
* Blake Peter Abt
* Ira Jamar Abair
* Ira Lamar Abair
* Chase Reyes Acy
* Lee Jamal Adell
* Tobias Asa Abts
* Derick C Acorda
* Otto Adan Aiton
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Aron Adan Aloan
* Aron Alan Aloan
* Amos Adan Aloan
* Amos Alan Aloan
* Arlie Gene Alan
* Arlie Rene Alan
* Otto Alan Aiton
* Nigel Al Alagna
* Cecil Al Alecca
* Al Isaias Alias
* Arlie Jere Alar
* Bradly L Aldaba
* Arlie Jewell Aw
* Emile Jere Dier
* Elijah Asa Dies
* Emile Gene Dien
* Emile Rene Dien
* Rey Reyes Eayrs
* Roy Reyes Eayrs
* Les Dewey Easly
* Ray Reyes Eayrs
* Earl E Deserres
* Eddie Derek Der
* Earle Deserres
* Stefan Asa Dess
* Steve Pete Dest
* Ezra E Deserres
* Shelby Bob Deso
* Royce Les Eayrs
* Eddie Ben Elden
* Eddie Ken Elden
* Eddie Ken Eiden
* Eddie Len Eiden
* Chi Derek Elick
* Lee Solomon Elm
* Eddie Len Elden
* Ali Keven Elian
* Lee Jewel Edell
* Arlie Leo Edlao
* Royce Wes Eayrs
* Ed Steven Ebsen
* Al Steven Ehsan
* Eddie Ben Eiden
* Reuben Ed Efurd
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* Earle Rene Bren
* Robert Rory Bro
* L Rocco Cachola
* L Royce Cachola
* Royce Rene Byrn
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Otto Adan Axton
* Otto Alan Axton
* Adrian Asa Bras
* Earle Gene Bren
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Leo Gene Debold
* Leo Jere Debold
* Isaias Asa Dais
* Andre Derek Dar
* Leonel E Debold
* Lionel E Debold
* Leo Pete Debold
* Leo Rene Debold
* N Royce Cicconi
* Arlie Gene Clan
* N Boyce Cicconi
* N Rocco Cicconi
* Bruce Jere Cubr
* Isaiah Asa Dais
* Arlie Rene Clan
* Arlie Jere Clar
* Cleo Asa Kazeck
* Dean Rory Roady
* Ryan Rory Roary
* Ed Luigi Riller
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elwood O Rohwer
* Elmo Rory Romey
* Ed Luigi Rigler
* Deon Rory Rhody
* Dion Rory Rhody
* Eli Rene Revier
* Eliseo E Revier
* Ed Luigi Ridler
* Drew Rory Riedy
* Doug Rory Rhudy
* Anibal Asa Rias
* Dino Rory Rondy
* Ivan Asa Salais
* Silas Asa Salsa
* Isaiah a Salais
* Isaias a Salais
* Thomas a Sanots
* Troy Asa Sanots
* Alva Asa Salvas
* Denis Asa Sanda
* Ira Dana Salais
* Cesar Ira Rosca
* Drew Rory Ruedy
* Dong Rory Rondy
* Donn Rory Rondy
* Neil Asa Sabins
* Eloy Asa Sagoes
* Truman Asa Ruts
* Emery Ty Ryneer
* Eli Gene Regier
* Eli Jere Regier
* Ryan Rory Reary
* Ed Steve Reaser
* Eliseo E Regier
* Elmo Rory Remey
* Eli Pete Regier
* Eli Rene Regier
* Ezra Rory Rarey
* Dana Rory Randy
* Dane Rory Randy
* Art Dana Rajtar
* Elmo Asa Rammer
* Donn Rory Randy
* Earl Rory Rarey
* Dino Rory Randy
* Dong Rory Randy
* Eli Gene Renier
* Eddy E Resendes
* Stefan Asa Ress
* Ed Dee Resendes
* Eli Jere Revier
* Eli Pete Revier
* Alva Rory Revay
* Eli Gene Revier
* Eddie Resendes
* Eli Rene Renier
* Eliseo E Renier
* Eli Jere Renier
* Eli Pete Renier
* Art Pete Rentar
* Art Rene Rentar
* Art Gene Rentar
* Art Jere Rentar
* Alva Asa Sarvas
* Emmitt Ty Tomey
* Emmett Ty Tumey
* Emile Pete Tiet
* Emmett Ty Tomey
* Isaiah Asa Vais
* Isaias Asa Vais
* Emmitt Ty Tumey
* Benito Ty Tunby
* Emile Jere Tier
* T Dusty Tatsuta
* T Rusty Tatsuta
* Noe Dana Talent
* Noel Asa Talent
* Emile Gene Tien
* Emile Rene Tien
* Stefan Asa Tess
* Steve Pete Test
* E Otha Vanasten
* Elijah Asa Wies
* Isaiah Asa Zais
* Emile Gene Wien
* Emile Rene Wien
* Emile Rene Zien
* Emile Jere Zier
* Isaias Asa Zais
* Emile Gene Zien
* Stefan Asa Wess
* Emile Rene Vien
* Emile Jere Vier
* Anibal Asa Vias
* Emile Gene Vien
* N Mike Wedekind
* Neil E Wedekind
* Isaiah Asa Wais
* Isaias Asa Wais
* Ali Gene Setias
* Ali Jere Setias
* Noe Rene Serens
* Moses Asa Sesma
* Louis Asa Shula
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Noe Pete Serens
* Ezra Asa Sayres
* Rueben E Sebers
* Reed Asa Savers
* Earl Asa Sayres
* Noe Gene Serens
* Noe Jere Serens
* Miles Asa Selma
* Myles Asa Selma
* Emile Gene Sien
* Thad Asa Tabatt
* Tuan Asa Tabatt
* Ed Teodoro Ster
* Louie Pete Sult
* Duane Pete Tadt
* Graham Asa Tags
* Leo Dana Tabolt
* Leon Asa Tabolt
* Antwan Asa Stas
* Al Luigi Sillas
* Ed Luigi Sirles
* Emile Rene Sien
* Emile Jere Sier
* Louis Asa Soula
* Al Teodoro Star
* Ollie Pete Slot
* Edison O Solies
* Shelby Bob Leso
* Stefan Asa Less
* Tony Lyle Lente
* Zane Lyle Lenze
* Bret Lyle Liebe
* Elijah Asa Lies
* Anibal Asa Lias
* Robt Lyle Libre
* King Lyle Lenke
* Lee Dana Layell
* Eddy Lyle Ledee
* Arlie Keven Lav
* Lee Dana Lavell
* Lyle Lyle Lelle
* Kent Lyle Lenke
* Theo Lyle Leete
* Trey Lyle Leete
* Gene Lyle Longe
* Gino Lyle Lynge
* Isaiah Asa Mais
* Cecil Eli Lucci
* Gene Lyle Lynge
* I Otha Masaitis
* C Mike Mehelich
* Isaias Asa Mais
* Eddy a Marander
* Cecil Ali Lucci
* Daryl Eli Lordi
* Earl Lyle Loree
* Gino Lyle Longe
* Daryl Ali Lordi
* Ollie Peter Lot
* Paul Lyle Loupe
* Ezra Lyle Loree
* Gary Lyle Lorge
* Alvaro R Krivak
* Cletus U Kubeck
* W Rocky Knknown
* Adrian Asa Kras
* Duane Pete Ladt
* Isaiah Asa Lais
* Robt Lyle Labre
* Lee Dana Ladell
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Keenan Asa Keks
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Stefan Asa Kess
* Isaias Asa Lais
* Kurt Lyle Larke
* Vern Lyle Larve
* Kirk Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Lee Dana Lasell
* Shane Pete Last
* Karl Lyle Larke
* Dane Lyle Lande
* Dino Lyle Lande
* Elmo Asa Lammel
* Dana Lyle Lande
* Zane Lyle Lanze
* Dirk Lyle Larde
* Dong Lyle Lande
* Donn Lyle Lande
* Stefan Asa Mess
* Genaro R Orengo
* Isreal Asa Oris
* Otto Everett or
* Adrian Asa Oras
* Al Teodoro Otar
* Santo Coy Ounsy
* Morgan Asa Orms
* Murray Asa Orms
* Teodoro O Omoto
* Steve Pete Oest
* Emile Gene Oien
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Leo Solomon Olm
* Emile Rene Oien
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raemer
* Eddy Asa Raider
* Eddy Asa Radder
* Eddy Asa Raeder
* Isaias Asa Rais
* Antwan a Rajtar
* Elmo Asa Raimer
* Isaiah Asa Rais
* Adrian Adan Rad
* Isaias Asa Pais
* Elijah Asa Pies
* Ollie Jewell Ow
* Isaiah Asa Pais
* Rupert Rory Pro
* Adrian Adam Rad
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Isaias a Narain
* Ivan Asa Narain
* Steve Pete Nest
* Ernie Peter Net
* Ed Steve Neisen
* Ed Steve Nessen
* Isaiah a Narain
* Shannon Z Naasz
* Odis Asa Nacion
* Anibal Asa Mias
* Al Luigi Millam
* Otto Asa Nanton
* Ira Dana Narain
* Olin Asa Nacion
* Otis Asa Nacion
* Ernie Keven Nev
* L Damon Odonald
* L Daron Odonald
* L Aaron Odonald
* L Carol Odonald
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* L Jarod Odonald
* Eddie Jere Oder
* Austin I Nissan
* Elliot O Nowlen
* Emile Jere Nier
* Ian Solomon Nim
* Neal Bob Obiano
* Noah Bob Obiano
* Elroy Ty Nygren
* Emery Ty Nyreen
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5733 "glurk"] (non-homophonic solutions) ==
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Angelo Lyle Gay
* Andre Reyes Day
* Shane Pete Mast
* Shane Pete Fast
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Dean Rory Ready
* Luis Rory Reily
* Gino Lyle Lange
* Louie Pete Ault
* Edison O Rosier
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Arlie Dewey Law
* Rob Dewey Embry
* Eli Dana Rapier
* Elmo Rory Ramey
* Ali Rufus Urias
* Chi Derek Edick
* Otis Asa Nation
* Ali Reyes Elias
* Art Solomon Tam
* Andre Jewel Daw
* Dino Lyle Linde
* Dino Lyle Lunde
* Dino Lyle Lynde
* Arlie Reyes Lay
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Dong Lyle Lunde
* Delmar Asa Olds
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Odis Asa Nation
* Leif Rory Reily
* Elmo Asa Raymer
* Hai Solomon Ihm
* Chi Derek Emick
* Daryl Al Ilardi
* Arlie Rey Emlay
* Chi Derek Enick
* Trevor O Howeth
* Louie Pete Hult
* Chet Asa Kazeck
* Shane Pete Kast
* M Vernon Ingemi
* Neil Asa Garing
* Shane Leo Eraso
* Israel E Gehrig
* Elijah Asa Fies
* Chi Derek Erick
* Trevor O Horeth
* Chi Derek Evick
* L Vernon Angela
* Elmo Adan Aumen
* Shane Peter Ast
* Elmo Alan Aumen
* Elmo Alan Armen
* Elmo Adan Armen
* Duane Reyes Ady
* Blake Peter Abt
* Chase Reyes Acy
* Derick C Acorda
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Elijah Asa Dies
* Shelby Bob Deso
* Royce Les Eayrs
* Chi Derek Elick
* Ali Keven Elian
* Royce Wes Eayrs
* Al Steven Ehsan
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* L Royce Cachola
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Arlie Gene Clan
* Arlie Rene Clan
* Cleo Asa Kazeck
* Dean Rory Roady
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elmo Rory Romey
* Ed Luigi Rigler
* Ed Luigi Ridler
* Doug Rory Rhudy
* Dino Rory Rondy
* Dong Rory Rondy
* Truman Asa Ruts
* Dana Rory Randy
* Dane Rory Randy
* Dino Rory Randy
* Dong Rory Randy
* Benito Ty Tunby
* Noel Asa Talent
* E Otha Vanasten
* Elijah Asa Wies
* N Mike Wedekind
* Ali Gene Setias
* Ali Jere Setias
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Louie Pete Sult
* Leo Dana Tabolt
* Leon Asa Tabolt
* Ed Luigi Sirles
* Al Teodoro Star
* Shelby Bob Leso
* Elijah Asa Lies
* Robt Lyle Libre
* Arlie Keven Lav
* Gino Lyle Lynge
* C Mike Mehelich
* Daryl Eli Lordi
* Gino Lyle Longe
* Daryl Ali Lordi
* Gary Lyle Lorge
* Cletus U Kubeck
* Duane Pete Ladt
* Robt Lyle Labre
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Kurt Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Shane Pete Last
* Dino Lyle Lande
* Dana Lyle Lande
* Dirk Lyle Larde
* Dong Lyle Lande
* Santo Coy Ounsy
* Morgan Asa Orms
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raimer
* Elijah Asa Pies
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Odis Asa Nacion
* Otis Asa Nacion
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* Elroy Ty Nygren
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5676 "PBFred"] ==
* Evil Anal Aziel
== From doranchak [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=30#p22403 (1)] [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=40#p22438 (2)]==
* A McNamara Scar
* Ate severed ear
* Trove Behemoth
* Spiro Motorist
* Laura Catapult
* Alice Venetian
* Agile Venetian
* Lebanon Enable
* Indiana Saudis
* Extras Adopted
* Athlete Lethal
* Achieve Lethal
* a Fine Venetian
* of Flanagan Fog
* to One Behemoth
* Extras Adapted
* Training Neat
* Chinese Eel Ice
* Artists Use Tau
* Our Bananas Ron
* Its Revered Sir
* Our Faraway Row
* Old Bikinis Don
* Of These Men Tom (or Of The Semen Tom)
* Greats To The Go
* Or I Was A Nation
* O He Was A Face Of
* [http://www.zodiackillerciphers.com/?p=152 Over 2,700 phrases from Project Gutenberg experiment]
* [https://docs.google.com/spreadsheets/d/13R16xILq6XIWTklErwZq7ltod7EG08-zeiG0AnAtsl4/edit?usp=sharing Another Project Gutenberg experiment, scanned 61.5 GB of text]
* [http://www.zodiackillerciphers.com/?p=467 From article], person names:
** Chastity Tracy
** Erica Natalie T
** Islami M Amelia
** Eddie Resendes
** Ernie Zerenner
** Aileen Enerlan
** Chitumu Eunice
** Ariyana Mariam
** Sripada Harish
** Ali Raja Mariam
** Arriaga Laura L
** Duitama David D
** Steve Menezes N
** Arriaza Laura L
** Arizala Maria M
** Adriana Laura L
** Aziz a Zahaniah
* [http://www.zodiackillerciphers.com/?p=467 From article], phrases / word combinations:
** Sarah The Horse
** Uncle Peter Cut
** Achieve Lethal
** Obscene Nelson
** Extreme Reuter
** Emperors Ropes
** Leigh The Haile
** Kane Pops Punks
** Gareth Tot Ergo
** Niece Gene Penn
** Drop Rarer Code
** Door Non-Encode
** Iraq Alan Again
** All Banana Alan
** Alice Venetian
** Laura Catapult
** Afghan Amalgam
** Reassess Scars
** Clara Cataract
** Shannon Encase
** Okinawa Nation
** Indiana Saudis
** Regan Adalard
** Drippy Peptide
** Outlet Erector
** Akira Canadian
** Adriana Marram
** Mary Nina Norma
** Robert Rory Bro
** Smile Pete List
** Mary Tate Terme
** Mary Gags Germs
** Ryan Amaya Gary
** Daniel Eye Andy
** Eats Bobs Bates
** Kill Baby Bulky
** Shit Pipe Poise
** Eric Alan Alien
** Slave Pete Last
** Extra War After
** Murder Eye Army
** Clara Fatal Act
** Encoded Odd CEO
** [http://zodiackillerciphers.com/z13wordsearch-results-2-sorted.txt List of 283 phrases / word combinations that use two words]
** [http://zodiackillerciphers.com/z13wordsearch-results-3-sorted.txt List of 1,283,443 phrases / word combinations that use three words]
* From another corpus test for [https://www.reddit.com/r/ZodiacKiller/comments/axqx4z/z13_my_name_is_cipher/ reddit post]:
** Chief of Africa
** Uncle Peter Cut
** of Hair It Is Hot
** of These Newton
** at Me O Son of Man
** a Wide Venetian
** a Ripe Venetian
** Avis, a Canadian
** India. Was, and Is.
** I Saw Alan Again
** I Was a Man Again
** I Had a Man Again
** Near a Way As Any
** Claus Asks Jack
** Guest at Otsego
** One Has a Name on
** One Had an Axe on
** As if a Canadian
** Oh No It It Is Not
** Is That As Art Is
** Nearer Eden and
** Niagara Day And
** [http://zodiackillerciphers.com/z13-corpus-solutions.txt Full unprocessed results]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4305&p=69616 More results from corpus scanning:]
** So I'm a Satanist
** So I'm a Fatalist (from glurk)
** A Dog, a Cat, a Goat
** or Steve Nelson
** As I Had an Asian
** a Kid: a Canadian
** Emperor's Ropes
** As Real As Auras
** That I Die, I Hate
** One Has a Name on
** I've Had an Axe in
** Spectate These
** if I Was a Nazi in
** I Eat a Banana in
** As I'm a Canadian
** I Was a Canadian
** Leave Helen All
** Edit As an Alien
** Shakalaka Mask
** Shit! a Natalist!
** Shit! a Fatalist!
** Shit! a Satanist!
** Is a Pagan Again
** Extra Caracter
** and Gamal Abdal
** Donut. It Stands.
** Al Is a Canadian
** Reign on Entire
** I've Had a Dane I.D.
** Least It Steals
** Ratio, Do You Try?
** Said As a Taoist

== From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6406 "Deryk"] ==
* Male, Initial: M.T.
== From [https://www.tapatalk.com/groups/zodiackillerfr/my-name-is-zodiac-t2276-s20.html#p139086 "MickCal"] ==
* OL STEVE NELSON
== From [https://discord.com/channels/996952324150931477/996952376894292018/1135335122527342604 "Toad"] ==
* AMIGO COLONIAL
== From [https://discord.com/channels/996952324150931477/996952376894292018/1033254655381217320 "Antisquid42"] ==
* John E. Heresh Jr.
* Donald LeLinde
* Neal O’Donovann
* Doug Lyle Laude
* Chip O. Kozowicz
* Seth Everett Sr.
* Andrew E. Levdal
* Paul Lyle Loupe
* Shiloh Oto List
* Juan O. Corona Jr.
* Frank X. LeLoafe
* Leo Solomon Olm
== From [http://zodiackillerciphers.com/z13_2_word_solutions.txt "rando"] ==
* [http://zodiackillerciphers.com/z13_2_word_solutions.txt 3,142 2-word solutions]

== Partial solution from [http://zodiackiller.21.forumer.com/viewtopic.php?p=119889#119889 "granny101"] ==
* ILLNEVETELLIT ("I'LL NEVER TELL IT", with the "R" missing)
== From [https://www.tapatalk.com/groups/zodiackillerfr/solution-to-the-challenge-t11196.html#p264079 "CipherS0luti0ns"] ==
* SOLVE REVEALS V
== From [https://discord.com/channels/996952324150931477/996952376894292018/1259617636715860028 "Jasper"] ==
* HOPE IT IS IN PHS (PHS assumed to be reference to Presidio Heights)

= Solutions that fit if you first reverse the cipher =

TODO

= Solutions that fit the ciphertext if you permit anagramming =

Rearranging the cipher text significantly reduces the constraints on possible solutions. As [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=20#p13716 "glurk"] points out, anagramming the 13 symbols permits a very large variety of possible solutions, which makes it nearly impossible to validate any given solution derived this way.

Here are some examples of solutions that arise from anagramming:

* [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=40#p13807 Small sampling from "sincos"]
* From doranchak:
** 13-letter English words that have the same letter distribution as the symbols of the cipher:
*** international, participation, concentration, interventions, investigating, participating, inappropriate, investigative, authoritarian, mediterranean, intentionally, accommodation, strengthening, commissioners, differentiate, collaborators, incorporation, unwillingness, mismanagement, superstitious, mathematician, nationalities, instantaneous, nationalistic, inconsistency, choreographer, preponderance, condescending, applicability, contingencies, indeterminate, sarcastically, temperamental, disillusioned, prerequisites, intelligences, irreplaceable, headquartered, reincarnation, proportionate, appropriating, inclusiveness, preservatives, ornamentation, uninteresting, incapacitated, contaminating, irrationality, abolitionists, improprieties, structuralist, sharecroppers, solicitations, intermarriage, arbitrariness, impermissible, disconnection, professorship, scintillating, insufficiency, spectroscopic, satisfactions
** Small sampling of 13-letter surnames that have the same letter distribution as the symbols of the cipher:
*** radhakrishnan, bhattacharjee, villavicencio, chattopadhyay, oluwatobiloba, degraffenreid, knappenberger, brandenburger, hebblethwaite, rathakrishnan, degraffenried, sahasrabuddhe, stamatopoulos, schlegelmilch, sastrowardoyo, konstantinova, muruganantham, thorsteinsson, madhusoodanan, wojciechowicz, hintermeister, klingenberger, vansteenkiste, raveendranath, blankenbiller, messerschmitt, abdollahzadeh, vlaisavljevic, stamatopoulou, giacomantonio, gebregziabher, gardarsdottir, blattenberger, agustiningsih, sverrisdottir, shirmohammadi, reichenbacher, schottenstein, christophoros, javakhishvili, sundareswaran, schiermeister, kaluhiokalani, natsvlishvili, monteferrante, ntakirutimana, derakhshandeh, winternheimer, spangenberger, liechtenstein, heiderscheidt, chandrarathne, shettlesworth
** [http://zodiackillerciphers.com/all-names-z13-list2-sorted.txt A sampling of 69,607 common first-last name combinations] that have the same letter distribution as the symbols of the cipher.
*** [http://zodiackillersite.com/viewtopic.php?p=18552#p18552 (Original broken forum link)]
* From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6376 Tom Voigt]:
** knickerbocker
** [http://zodiackiller.21.forumer.com/viewtopic.php?p=120299#120299 aintgonnatell]
* From [http://www.santarosahitchhikermurders.com/ Deb Silva]:
** [http://en.wikipedia.org/wiki/Bobby_Beausoleil Bob Beausoleil]
* From Anonymous:
** Jimmy Phillips (also credited to [http://zodiackiller.fr.yuku.com/topic/3827/Jimmy-Phillips alanbenjy])
* From Christer Böke:
** Frank Frazetta ([http://zodiackillersite.com/viewtopic.php?f=63&t=1275 Tim Holt] was drawn by Frank Bollle and Frank Frazetta)
** Grant Santiago
* From [https://www.tapatalk.com/groups/zodiackillerfr/simple-solve-for-the-my-name-is-t8738.html#p145360 jaydeezodiachunter]:
** Debbie Faraday

= Solutions that fit if you relax other constraints of the cipher =

Solutions that fit if you allow all three "circled 8" symbols to be wildcards:
* From Michael Kelleher:
** thebigsecrete
Solutions that are produced via multiple operations:
* From [http://www.zodiackillerciphers.com/?p=46 Lyndon Lafferty]:
** NAME GRANT, or NAME IS GRANT
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/detailed-solution-to-z13-and-z32/ Faycal Ziraoui's solution]
A solution that applies the 408 key and interprets some symbols as nulls:
* from [http://zodiackiller.fr.yuku.com/topic/6839/Zodiacs-Name-using-408-Key Rembrandt]:
** ED SHAW
Solutions with one name part in the middle, and another name part split in half and written backwards:
* [http://www.zodiackillersite.com/viewtopic.php?p=69126#p69126 DEBBIE FARADAY]

= Other interpretations =

* "My name is" contains 8 letters. The cipher text contains 8 letters and 5 special symbols. The special symbols contain Zodiac's name and the rest just mean "My name is" (Source: Jeppesen)
* [https://www.tapatalk.com/groups/zodiackillerfr/general-book-discussion-for-hunted-the-zodiac-murd-t10141.html#p197345 "Set addition" interpretation of Z13 by Doug Oswell], resulting in solution: "FROM TED KACZYNS[K]I"
* [https://www.tapatalk.com/groups/zodiackillerfr/paul-astrup-s-theory-meteorological-symbols-challe-t10261.html#p202558 Weather symbols]
* The line after "My name is" is roughly above symbols that resemble "Tom" spelled backwards. (Source: David Cauley via YouTube comments)

Z13 Solutions

2024-07-07T21:50:11Z

Admin: /* From "CipherS0luti0ns" */

= Solutions that fit the ciphertext as is =

This section only shows proposed solutions that fit the cipher text "as is". No anagramming or other re-arrangements are used here, and the cipher is considered to be strictly a substitution cipher. Solutions that permit anagramming are very easy to come by, as there are several billion possible string combinations to choose from. Solutions that do not require anagramming are still numerous, however, which increases the difficulty of knowing which one is correct.

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=50&t=1390&p=24191#p24190 "Quill"] ==
* Eddie Penerden
* Stan T E Case (using "8"s as spaces)
* Greg N A Vega (using "8"s as spaces)

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5677 "glurk"] (homophonic solutions) ==
* Steve Pete West
* Adrian a Harrah
* Shannon E Nease
* Steve Pete Best
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Eddie Gene Oden
* Steve Pete Vest
* Barney E Yearby
* Gene Lyle Lange
* Eddie Gene Eden
* Ed Steven Eisen
* E Alva Vanallen
* Angelo Lyle Gay
* Eddie Rene Oden
* Isreal a Sarris
* Carl Bob Abarca
* Elliot O Roller
* Andre Reyes Day
* Ed Steve Nelsen
* Shane Pete East
* Lee Gene Levell
* Eddie Rene Eden
* Rueben E Segers
* Rueben E Severs
* Eddie Gene Aden
* Eddie Dewey Dew
* Shane Pete Mast
* Ed Steve Reeser
* Ed Steve Reiser
* Lee Rene Levell
* Neal Alan Amann
* Sean Lyle Lease
* Otto Alan Alton
* Otto Alan Acton
* Otto Alan Aston
* Otto Alan Anton
* Eddie Rene Aden
* Lee Jamal Abell
* Andre Gene Adan
* Reed Alan Ahern
* Shane Pete Fast
* Elliot O Yokley
* Elliot O Soules
* Lee Pete Levell
* Ira Lamar Adair
* Neil Lyle Laine
* Teodoro Tom Ott
* Otto Adam Altom
* Noah Alan Amann
* Eddy Alan Alden
* Lee Jewel Ezell
* Cory Bob Abarca
* Andre Rene Adan
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Earle Gene Wren
* Dean Rory Ready
* Dana Bob Obando
* Luis Rory Reily
* Otto Asa Santos
* Eric Asa Rapier
* Gino Lyle Lange
* Eddy Alan Arden
* Kent Lyle Linke
* Andre Dewey Daw
* Eddie Les Eades
* Louie Pete Ault
* Eddie Jewel Dew
* Ian Reyes Ennis
* Edison O Rosier
* Ollie Lee Enloe
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Ira Jamar Adair
* Earle Rene Wren
* Ernie Dewey New
* Lee Jewel Ewell
* Eddie Wes Eades
* Drew Rory Reedy
* Al Isaias Arias
* Ollie Derek Lor
* Cary Bob Abarca
* Emile Gene Lien
* Arlie Dewey Law
* Ollie Dewey Low
* Rob Dewey Embry
* Curt Bob Abarca
* Earl Asa Laurel
* Stefan Asa Hess
* Eddie Reyes Dey
* Eli Dana Rapier
* Dane Bob Obando
* Elmo Rory Ramey
* Lee Jere Levell
* Ali Rufus Urias
* Emile Rene Lien
* Eddie Jere Eder
* Stan Lyle Lease
* Chi Derek Edick
* Earle Gene Oren
* Emile Gene Bien
* Earle Gene Uren
* Arturo Rory Tao
* Otis Asa Nation
* Genaro Rory Ngo
* Dane Lyle Linde
* Dane Lyle Lynde
* Dane Lyle Lunde
* Scot Lyle Loose
* Ali Reyes Elias
* Art Solomon Tam
* Donn Bob Obando
* Dino Bob Obando
* Andre Jewel Daw
* Neal Adan Amann
* Emile Rene Bien
* Otto Adan Alton
* Earle Rene Uren
* Otto Adan Acton
* Earle Rene Oren
* Otto Adan Anton
* Otto Adan Aston
* Dallas Asa Olds
* Erik Asa Rapier
* Reed Adan Ahern
* Ernie Jewel New
* Donn Lyle Linde
* Dino Lyle Linde
* Donn Lyle Lynde
* Dino Lyle Lunde
* Donn Lyle Lunde
* Dino Lyle Lynde
* Dong Bob Obando
* Teodoro Tod Ott
* Stefan Asa Bess
* Noah Adan Amann
* Arlie Jewel Law
* Issac Jc Ocasio
* Arlie Reyes Lay
* Ed Teodoro Ater
* Ollie Jewel Low
* Eddy Adan Alden
* Shad Lyle Lease
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Shon Lyle Loose
* Dong Lyle Lunde
* Ollie Reyes Loy
* Stefan Asa Ness
* Earle Dewey Rew
* Reed Asa Sayers
* Anibal Asa Dias
* Noe Reyes Edens
* Delmar Asa Olds
* Isreal Al Abril
* Isreal Al April
* Earle Reyes Rey
* Ernie Les Eanes
* Eddy Adan Arden
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Ernie Reyes Ney
* Morgan Asa Arms
* Olin Asa Nation
* Lou Solomon Ulm
* Ernie Wes Eanes
* Ernie Rey Edney
* Odis Asa Nation
* Murray Asa Arms
* Noe Reyes Evens
* Ollie Dee Enloe
* Leif Rory Reily
* Elmo Asa Raymer
* Isaiah Asa Sais
* Anibal Asa Bias
* Ollie Jere Flor
* Reed Asa Sagers
* Reed Asa Sauers
* Stefan Asa Vess
* Stefan Asa Jess
* Stefan Asa Gess
* Ezra Asa Laurel
* Erin Asa Rapier
* Emile Jere Mier
* Emile Jere Pier
* Emile Jere Bier
* Earle Jewel Rew
* Emile Jere Wier
* Emile Jere Kier
* Anibal Asa Sias
* Isaias Asa Sais
* Paris Asa Serpa
* Arlie Jere Klar
* Luigi Gil Ifill
* Hai Solomon Ihm
* Darell L Ilardi
* Chi Derek Emick
* Eddie Lee Emdee
* Daryl Al Ilardi
* Arlie Rey Emlay
* Eddie Rene Iden
* Chi Derek Enick
* Earle Rene Hren
* Trevor O Howeth
* Earle Gene Hren
* Duncan Asa Ends
* Danial Asa Ends
* Louie Pete Hult
* Eddie Gene Iden
* Chas Asa Kasack
* Clay Asa Kasack
* Lee Jewel Euell
* Chad Asa Kasack
* Ian Dana Katnik
* Chet Asa Kazeck
* Shane Pete Kast
* Leo Jewel Etoll
* Ian Dana Kamnik
* M Keenan Ingemi
* M Vernon Ingemi
* Ernie Jere Iner
* Eddie Dee Emdee
* Isaias Asa Kais
* Ed Steven Elsen
* Steve Pete Jest
* Isaiah Asa Kais
* Theron O Howeth
* Neil Asa Garing
* Ernie Wes Ennes
* Noah Asa Galang
* Shane Leo Eraso
* Steve Pete Gest
* Emile Jere Gier
* Israel E Gehrig
* N Eugene Genung
* Neal Asa Galang
* Elijah Asa Fies
* Steve Pete Fest
* Eli Peter Etier
* Ed Steven Essen
* Stefan Asa Fess
* Chi Derek Erick
* Ollie Pete Flot
* Earle Pete Fret
* Ernie Ben Ennen
* Emile Jere Hier
* Ernie Len Ennen
* Ernie Ken Ennen
* Theron O Horeth
* Trevor O Horeth
* Lee Bo Holowell
* Chi Derek Evick
* Ernie Les Ennes
* Adrian Asa Gras
* Earle Gene Gren
* Noe Reyes Ewens
* Ollie Jere Glor
* Shad Asa Habash
* Stan Asa Habash
* Earle Rene Gren
* Sean Asa Habash
* Aldo Alan Ardan
* Andy Adan Ardan
* Art Jamal Antal
* Aldo Adan Ardan
* Eli Jamal Ariel
* Elijah Al Ariel
* Andy Alan Ardan
* Dorian Asa Ards
* Leland N Analla
* R Keenan Andera
* Lee Jamal Amell
* Ty Isaiah Amith
* L Vernon Angela
* Antwan Al Antal
* R Vernon Andera
* L Keenan Angela
* Ed Isaias Aries
* Art Jamal Attal
* Elmo Adan Aumen
* Shane Peter Ast
* Antwan Al Attal
* Otto Alan Auton
* Isreal Al Avril
* Elmo Alan Aumen
* Otto Adan Auton
* Elmo Alan Armen
* Norman Asa Arns
* Isreal Asa Aris
* Elmo Adan Armen
* Alva Adan Arvan
* Alva Alan Arvan
* Otto Adan Arton
* Otto Alan Arton
* Otto Adan Afton
* Otto Alan Afton
* Eddie Jere Ader
* Duane Reyes Ady
* Isaias Adam Aid
* Isaias Adan Aid
* Isaiah Adam Aid
* Isaiah Adan Aid
* Lyle Bob Abella
* Blake Peter Abt
* Ira Jamar Abair
* Ira Lamar Abair
* Chase Reyes Acy
* Lee Jamal Adell
* Tobias Asa Abts
* Derick C Acorda
* Otto Adan Aiton
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Aron Adan Aloan
* Aron Alan Aloan
* Amos Adan Aloan
* Amos Alan Aloan
* Arlie Gene Alan
* Arlie Rene Alan
* Otto Alan Aiton
* Nigel Al Alagna
* Cecil Al Alecca
* Al Isaias Alias
* Arlie Jere Alar
* Bradly L Aldaba
* Arlie Jewell Aw
* Emile Jere Dier
* Elijah Asa Dies
* Emile Gene Dien
* Emile Rene Dien
* Rey Reyes Eayrs
* Roy Reyes Eayrs
* Les Dewey Easly
* Ray Reyes Eayrs
* Earl E Deserres
* Eddie Derek Der
* Earle Deserres
* Stefan Asa Dess
* Steve Pete Dest
* Ezra E Deserres
* Shelby Bob Deso
* Royce Les Eayrs
* Eddie Ben Elden
* Eddie Ken Elden
* Eddie Ken Eiden
* Eddie Len Eiden
* Chi Derek Elick
* Lee Solomon Elm
* Eddie Len Elden
* Ali Keven Elian
* Lee Jewel Edell
* Arlie Leo Edlao
* Royce Wes Eayrs
* Ed Steven Ebsen
* Al Steven Ehsan
* Eddie Ben Eiden
* Reuben Ed Efurd
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* Earle Rene Bren
* Robert Rory Bro
* L Rocco Cachola
* L Royce Cachola
* Royce Rene Byrn
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Otto Adan Axton
* Otto Alan Axton
* Adrian Asa Bras
* Earle Gene Bren
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Leo Gene Debold
* Leo Jere Debold
* Isaias Asa Dais
* Andre Derek Dar
* Leonel E Debold
* Lionel E Debold
* Leo Pete Debold
* Leo Rene Debold
* N Royce Cicconi
* Arlie Gene Clan
* N Boyce Cicconi
* N Rocco Cicconi
* Bruce Jere Cubr
* Isaiah Asa Dais
* Arlie Rene Clan
* Arlie Jere Clar
* Cleo Asa Kazeck
* Dean Rory Roady
* Ryan Rory Roary
* Ed Luigi Riller
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elwood O Rohwer
* Elmo Rory Romey
* Ed Luigi Rigler
* Deon Rory Rhody
* Dion Rory Rhody
* Eli Rene Revier
* Eliseo E Revier
* Ed Luigi Ridler
* Drew Rory Riedy
* Doug Rory Rhudy
* Anibal Asa Rias
* Dino Rory Rondy
* Ivan Asa Salais
* Silas Asa Salsa
* Isaiah a Salais
* Isaias a Salais
* Thomas a Sanots
* Troy Asa Sanots
* Alva Asa Salvas
* Denis Asa Sanda
* Ira Dana Salais
* Cesar Ira Rosca
* Drew Rory Ruedy
* Dong Rory Rondy
* Donn Rory Rondy
* Neil Asa Sabins
* Eloy Asa Sagoes
* Truman Asa Ruts
* Emery Ty Ryneer
* Eli Gene Regier
* Eli Jere Regier
* Ryan Rory Reary
* Ed Steve Reaser
* Eliseo E Regier
* Elmo Rory Remey
* Eli Pete Regier
* Eli Rene Regier
* Ezra Rory Rarey
* Dana Rory Randy
* Dane Rory Randy
* Art Dana Rajtar
* Elmo Asa Rammer
* Donn Rory Randy
* Earl Rory Rarey
* Dino Rory Randy
* Dong Rory Randy
* Eli Gene Renier
* Eddy E Resendes
* Stefan Asa Ress
* Ed Dee Resendes
* Eli Jere Revier
* Eli Pete Revier
* Alva Rory Revay
* Eli Gene Revier
* Eddie Resendes
* Eli Rene Renier
* Eliseo E Renier
* Eli Jere Renier
* Eli Pete Renier
* Art Pete Rentar
* Art Rene Rentar
* Art Gene Rentar
* Art Jere Rentar
* Alva Asa Sarvas
* Emmitt Ty Tomey
* Emmett Ty Tumey
* Emile Pete Tiet
* Emmett Ty Tomey
* Isaiah Asa Vais
* Isaias Asa Vais
* Emmitt Ty Tumey
* Benito Ty Tunby
* Emile Jere Tier
* T Dusty Tatsuta
* T Rusty Tatsuta
* Noe Dana Talent
* Noel Asa Talent
* Emile Gene Tien
* Emile Rene Tien
* Stefan Asa Tess
* Steve Pete Test
* E Otha Vanasten
* Elijah Asa Wies
* Isaiah Asa Zais
* Emile Gene Wien
* Emile Rene Wien
* Emile Rene Zien
* Emile Jere Zier
* Isaias Asa Zais
* Emile Gene Zien
* Stefan Asa Wess
* Emile Rene Vien
* Emile Jere Vier
* Anibal Asa Vias
* Emile Gene Vien
* N Mike Wedekind
* Neil E Wedekind
* Isaiah Asa Wais
* Isaias Asa Wais
* Ali Gene Setias
* Ali Jere Setias
* Noe Rene Serens
* Moses Asa Sesma
* Louis Asa Shula
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Noe Pete Serens
* Ezra Asa Sayres
* Rueben E Sebers
* Reed Asa Savers
* Earl Asa Sayres
* Noe Gene Serens
* Noe Jere Serens
* Miles Asa Selma
* Myles Asa Selma
* Emile Gene Sien
* Thad Asa Tabatt
* Tuan Asa Tabatt
* Ed Teodoro Ster
* Louie Pete Sult
* Duane Pete Tadt
* Graham Asa Tags
* Leo Dana Tabolt
* Leon Asa Tabolt
* Antwan Asa Stas
* Al Luigi Sillas
* Ed Luigi Sirles
* Emile Rene Sien
* Emile Jere Sier
* Louis Asa Soula
* Al Teodoro Star
* Ollie Pete Slot
* Edison O Solies
* Shelby Bob Leso
* Stefan Asa Less
* Tony Lyle Lente
* Zane Lyle Lenze
* Bret Lyle Liebe
* Elijah Asa Lies
* Anibal Asa Lias
* Robt Lyle Libre
* King Lyle Lenke
* Lee Dana Layell
* Eddy Lyle Ledee
* Arlie Keven Lav
* Lee Dana Lavell
* Lyle Lyle Lelle
* Kent Lyle Lenke
* Theo Lyle Leete
* Trey Lyle Leete
* Gene Lyle Longe
* Gino Lyle Lynge
* Isaiah Asa Mais
* Cecil Eli Lucci
* Gene Lyle Lynge
* I Otha Masaitis
* C Mike Mehelich
* Isaias Asa Mais
* Eddy a Marander
* Cecil Ali Lucci
* Daryl Eli Lordi
* Earl Lyle Loree
* Gino Lyle Longe
* Daryl Ali Lordi
* Ollie Peter Lot
* Paul Lyle Loupe
* Ezra Lyle Loree
* Gary Lyle Lorge
* Alvaro R Krivak
* Cletus U Kubeck
* W Rocky Knknown
* Adrian Asa Kras
* Duane Pete Ladt
* Isaiah Asa Lais
* Robt Lyle Labre
* Lee Dana Ladell
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Keenan Asa Keks
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Stefan Asa Kess
* Isaias Asa Lais
* Kurt Lyle Larke
* Vern Lyle Larve
* Kirk Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Lee Dana Lasell
* Shane Pete Last
* Karl Lyle Larke
* Dane Lyle Lande
* Dino Lyle Lande
* Elmo Asa Lammel
* Dana Lyle Lande
* Zane Lyle Lanze
* Dirk Lyle Larde
* Dong Lyle Lande
* Donn Lyle Lande
* Stefan Asa Mess
* Genaro R Orengo
* Isreal Asa Oris
* Otto Everett or
* Adrian Asa Oras
* Al Teodoro Otar
* Santo Coy Ounsy
* Morgan Asa Orms
* Murray Asa Orms
* Teodoro O Omoto
* Steve Pete Oest
* Emile Gene Oien
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Leo Solomon Olm
* Emile Rene Oien
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raemer
* Eddy Asa Raider
* Eddy Asa Radder
* Eddy Asa Raeder
* Isaias Asa Rais
* Antwan a Rajtar
* Elmo Asa Raimer
* Isaiah Asa Rais
* Adrian Adan Rad
* Isaias Asa Pais
* Elijah Asa Pies
* Ollie Jewell Ow
* Isaiah Asa Pais
* Rupert Rory Pro
* Adrian Adam Rad
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Isaias a Narain
* Ivan Asa Narain
* Steve Pete Nest
* Ernie Peter Net
* Ed Steve Neisen
* Ed Steve Nessen
* Isaiah a Narain
* Shannon Z Naasz
* Odis Asa Nacion
* Anibal Asa Mias
* Al Luigi Millam
* Otto Asa Nanton
* Ira Dana Narain
* Olin Asa Nacion
* Otis Asa Nacion
* Ernie Keven Nev
* L Damon Odonald
* L Daron Odonald
* L Aaron Odonald
* L Carol Odonald
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* L Jarod Odonald
* Eddie Jere Oder
* Austin I Nissan
* Elliot O Nowlen
* Emile Jere Nier
* Ian Solomon Nim
* Neal Bob Obiano
* Noah Bob Obiano
* Elroy Ty Nygren
* Emery Ty Nyreen
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5733 "glurk"] (non-homophonic solutions) ==
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Angelo Lyle Gay
* Andre Reyes Day
* Shane Pete Mast
* Shane Pete Fast
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Dean Rory Ready
* Luis Rory Reily
* Gino Lyle Lange
* Louie Pete Ault
* Edison O Rosier
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Arlie Dewey Law
* Rob Dewey Embry
* Eli Dana Rapier
* Elmo Rory Ramey
* Ali Rufus Urias
* Chi Derek Edick
* Otis Asa Nation
* Ali Reyes Elias
* Art Solomon Tam
* Andre Jewel Daw
* Dino Lyle Linde
* Dino Lyle Lunde
* Dino Lyle Lynde
* Arlie Reyes Lay
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Dong Lyle Lunde
* Delmar Asa Olds
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Odis Asa Nation
* Leif Rory Reily
* Elmo Asa Raymer
* Hai Solomon Ihm
* Chi Derek Emick
* Daryl Al Ilardi
* Arlie Rey Emlay
* Chi Derek Enick
* Trevor O Howeth
* Louie Pete Hult
* Chet Asa Kazeck
* Shane Pete Kast
* M Vernon Ingemi
* Neil Asa Garing
* Shane Leo Eraso
* Israel E Gehrig
* Elijah Asa Fies
* Chi Derek Erick
* Trevor O Horeth
* Chi Derek Evick
* L Vernon Angela
* Elmo Adan Aumen
* Shane Peter Ast
* Elmo Alan Aumen
* Elmo Alan Armen
* Elmo Adan Armen
* Duane Reyes Ady
* Blake Peter Abt
* Chase Reyes Acy
* Derick C Acorda
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Elijah Asa Dies
* Shelby Bob Deso
* Royce Les Eayrs
* Chi Derek Elick
* Ali Keven Elian
* Royce Wes Eayrs
* Al Steven Ehsan
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* L Royce Cachola
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Arlie Gene Clan
* Arlie Rene Clan
* Cleo Asa Kazeck
* Dean Rory Roady
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elmo Rory Romey
* Ed Luigi Rigler
* Ed Luigi Ridler
* Doug Rory Rhudy
* Dino Rory Rondy
* Dong Rory Rondy
* Truman Asa Ruts
* Dana Rory Randy
* Dane Rory Randy
* Dino Rory Randy
* Dong Rory Randy
* Benito Ty Tunby
* Noel Asa Talent
* E Otha Vanasten
* Elijah Asa Wies
* N Mike Wedekind
* Ali Gene Setias
* Ali Jere Setias
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Louie Pete Sult
* Leo Dana Tabolt
* Leon Asa Tabolt
* Ed Luigi Sirles
* Al Teodoro Star
* Shelby Bob Leso
* Elijah Asa Lies
* Robt Lyle Libre
* Arlie Keven Lav
* Gino Lyle Lynge
* C Mike Mehelich
* Daryl Eli Lordi
* Gino Lyle Longe
* Daryl Ali Lordi
* Gary Lyle Lorge
* Cletus U Kubeck
* Duane Pete Ladt
* Robt Lyle Labre
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Kurt Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Shane Pete Last
* Dino Lyle Lande
* Dana Lyle Lande
* Dirk Lyle Larde
* Dong Lyle Lande
* Santo Coy Ounsy
* Morgan Asa Orms
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raimer
* Elijah Asa Pies
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Odis Asa Nacion
* Otis Asa Nacion
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* Elroy Ty Nygren
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5676 "PBFred"] ==
* Evil Anal Aziel
== From doranchak [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=30#p22403 (1)] [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=40#p22438 (2)]==
* A McNamara Scar
* Ate severed ear
* Trove Behemoth
* Spiro Motorist
* Laura Catapult
* Alice Venetian
* Agile Venetian
* Lebanon Enable
* Indiana Saudis
* Extras Adopted
* Athlete Lethal
* Achieve Lethal
* a Fine Venetian
* of Flanagan Fog
* to One Behemoth
* Extras Adapted
* Training Neat
* Chinese Eel Ice
* Artists Use Tau
* Our Bananas Ron
* Its Revered Sir
* Our Faraway Row
* Old Bikinis Don
* Of These Men Tom (or Of The Semen Tom)
* Greats To The Go
* Or I Was A Nation
* O He Was A Face Of
* [http://www.zodiackillerciphers.com/?p=152 Over 2,700 phrases from Project Gutenberg experiment]
* [https://docs.google.com/spreadsheets/d/13R16xILq6XIWTklErwZq7ltod7EG08-zeiG0AnAtsl4/edit?usp=sharing Another Project Gutenberg experiment, scanned 61.5 GB of text]
* [http://www.zodiackillerciphers.com/?p=467 From article], person names:
** Chastity Tracy
** Erica Natalie T
** Islami M Amelia
** Eddie Resendes
** Ernie Zerenner
** Aileen Enerlan
** Chitumu Eunice
** Ariyana Mariam
** Sripada Harish
** Ali Raja Mariam
** Arriaga Laura L
** Duitama David D
** Steve Menezes N
** Arriaza Laura L
** Arizala Maria M
** Adriana Laura L
** Aziz a Zahaniah
* [http://www.zodiackillerciphers.com/?p=467 From article], phrases / word combinations:
** Sarah The Horse
** Uncle Peter Cut
** Achieve Lethal
** Obscene Nelson
** Extreme Reuter
** Emperors Ropes
** Leigh The Haile
** Kane Pops Punks
** Gareth Tot Ergo
** Niece Gene Penn
** Drop Rarer Code
** Door Non-Encode
** Iraq Alan Again
** All Banana Alan
** Alice Venetian
** Laura Catapult
** Afghan Amalgam
** Reassess Scars
** Clara Cataract
** Shannon Encase
** Okinawa Nation
** Indiana Saudis
** Regan Adalard
** Drippy Peptide
** Outlet Erector
** Akira Canadian
** Adriana Marram
** Mary Nina Norma
** Robert Rory Bro
** Smile Pete List
** Mary Tate Terme
** Mary Gags Germs
** Ryan Amaya Gary
** Daniel Eye Andy
** Eats Bobs Bates
** Kill Baby Bulky
** Shit Pipe Poise
** Eric Alan Alien
** Slave Pete Last
** Extra War After
** Murder Eye Army
** Clara Fatal Act
** Encoded Odd CEO
** [http://zodiackillerciphers.com/z13wordsearch-results-2-sorted.txt List of 283 phrases / word combinations that use two words]
** [http://zodiackillerciphers.com/z13wordsearch-results-3-sorted.txt List of 1,283,443 phrases / word combinations that use three words]
* From another corpus test for [https://www.reddit.com/r/ZodiacKiller/comments/axqx4z/z13_my_name_is_cipher/ reddit post]:
** Chief of Africa
** Uncle Peter Cut
** of Hair It Is Hot
** of These Newton
** at Me O Son of Man
** a Wide Venetian
** a Ripe Venetian
** Avis, a Canadian
** India. Was, and Is.
** I Saw Alan Again
** I Was a Man Again
** I Had a Man Again
** Near a Way As Any
** Claus Asks Jack
** Guest at Otsego
** One Has a Name on
** One Had an Axe on
** As if a Canadian
** Oh No It It Is Not
** Is That As Art Is
** Nearer Eden and
** Niagara Day And
** [http://zodiackillerciphers.com/z13-corpus-solutions.txt Full unprocessed results]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4305&p=69616 More results from corpus scanning:]
** So I'm a Satanist
** So I'm a Fatalist (from glurk)
** A Dog, a Cat, a Goat
** or Steve Nelson
** As I Had an Asian
** a Kid: a Canadian
** Emperor's Ropes
** As Real As Auras
** That I Die, I Hate
** One Has a Name on
** I've Had an Axe in
** Spectate These
** if I Was a Nazi in
** I Eat a Banana in
** As I'm a Canadian
** I Was a Canadian
** Leave Helen All
** Edit As an Alien
** Shakalaka Mask
** Shit! a Natalist!
** Shit! a Fatalist!
** Shit! a Satanist!
** Is a Pagan Again
** Extra Caracter
** and Gamal Abdal
** Donut. It Stands.
** Al Is a Canadian
** Reign on Entire
** I've Had a Dane I.D.
** Least It Steals
** Ratio, Do You Try?
** Said As a Taoist

== From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6406 "Deryk"] ==
* Male, Initial: M.T.
== From [https://www.tapatalk.com/groups/zodiackillerfr/my-name-is-zodiac-t2276-s20.html#p139086 "MickCal"] ==
* OL STEVE NELSON
== From [https://discord.com/channels/996952324150931477/996952376894292018/1135335122527342604 "Toad"] ==
* AMIGO COLONIAL
== From [https://discord.com/channels/996952324150931477/996952376894292018/1033254655381217320 "Antisquid42"] ==
* John E. Heresh Jr.
* Donald LeLinde
* Neal O’Donovann
* Doug Lyle Laude
* Chip O. Kozowicz
* Seth Everett Sr.
* Andrew E. Levdal
* Paul Lyle Loupe
* Shiloh Oto List
* Juan O. Corona Jr.
* Frank X. LeLoafe
* Leo Solomon Olm
== From [http://zodiackillerciphers.com/z13_2_word_solutions.txt "rando"] ==
* [http://zodiackillerciphers.com/z13_2_word_solutions.txt 3,142 2-word solutions]

== Partial solution from [http://zodiackiller.21.forumer.com/viewtopic.php?p=119889#119889 "granny101"] ==
* ILLNEVETELLIT ("I'LL NEVER TELL IT", with the "R" missing)
== From [https://www.tapatalk.com/groups/zodiackillerfr/solution-to-the-challenge-t11196.html#p264079 "CipherS0luti0ns"] ==
* SOLVE REVEALS V
== From [https://discord.com/channels/996952324150931477/996952376894292018/1259617636715860028 "Jasper"] ==
* HOPE IT IS IN PHS

= Solutions that fit if you first reverse the cipher =

TODO

= Solutions that fit the ciphertext if you permit anagramming =

Rearranging the cipher text significantly reduces the constraints on possible solutions. As [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=20#p13716 "glurk"] points out, anagramming the 13 symbols permits a very large variety of possible solutions, which makes it nearly impossible to validate any given solution derived this way.

Here are some examples of solutions that arise from anagramming:

* [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=40#p13807 Small sampling from "sincos"]
* From doranchak:
** 13-letter English words that have the same letter distribution as the symbols of the cipher:
*** international, participation, concentration, interventions, investigating, participating, inappropriate, investigative, authoritarian, mediterranean, intentionally, accommodation, strengthening, commissioners, differentiate, collaborators, incorporation, unwillingness, mismanagement, superstitious, mathematician, nationalities, instantaneous, nationalistic, inconsistency, choreographer, preponderance, condescending, applicability, contingencies, indeterminate, sarcastically, temperamental, disillusioned, prerequisites, intelligences, irreplaceable, headquartered, reincarnation, proportionate, appropriating, inclusiveness, preservatives, ornamentation, uninteresting, incapacitated, contaminating, irrationality, abolitionists, improprieties, structuralist, sharecroppers, solicitations, intermarriage, arbitrariness, impermissible, disconnection, professorship, scintillating, insufficiency, spectroscopic, satisfactions
** Small sampling of 13-letter surnames that have the same letter distribution as the symbols of the cipher:
*** radhakrishnan, bhattacharjee, villavicencio, chattopadhyay, oluwatobiloba, degraffenreid, knappenberger, brandenburger, hebblethwaite, rathakrishnan, degraffenried, sahasrabuddhe, stamatopoulos, schlegelmilch, sastrowardoyo, konstantinova, muruganantham, thorsteinsson, madhusoodanan, wojciechowicz, hintermeister, klingenberger, vansteenkiste, raveendranath, blankenbiller, messerschmitt, abdollahzadeh, vlaisavljevic, stamatopoulou, giacomantonio, gebregziabher, gardarsdottir, blattenberger, agustiningsih, sverrisdottir, shirmohammadi, reichenbacher, schottenstein, christophoros, javakhishvili, sundareswaran, schiermeister, kaluhiokalani, natsvlishvili, monteferrante, ntakirutimana, derakhshandeh, winternheimer, spangenberger, liechtenstein, heiderscheidt, chandrarathne, shettlesworth
** [http://zodiackillerciphers.com/all-names-z13-list2-sorted.txt A sampling of 69,607 common first-last name combinations] that have the same letter distribution as the symbols of the cipher.
*** [http://zodiackillersite.com/viewtopic.php?p=18552#p18552 (Original broken forum link)]
* From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6376 Tom Voigt]:
** knickerbocker
** [http://zodiackiller.21.forumer.com/viewtopic.php?p=120299#120299 aintgonnatell]
* From [http://www.santarosahitchhikermurders.com/ Deb Silva]:
** [http://en.wikipedia.org/wiki/Bobby_Beausoleil Bob Beausoleil]
* From Anonymous:
** Jimmy Phillips (also credited to [http://zodiackiller.fr.yuku.com/topic/3827/Jimmy-Phillips alanbenjy])
* From Christer Böke:
** Frank Frazetta ([http://zodiackillersite.com/viewtopic.php?f=63&t=1275 Tim Holt] was drawn by Frank Bollle and Frank Frazetta)
** Grant Santiago
* From [https://www.tapatalk.com/groups/zodiackillerfr/simple-solve-for-the-my-name-is-t8738.html#p145360 jaydeezodiachunter]:
** Debbie Faraday

= Solutions that fit if you relax other constraints of the cipher =

Solutions that fit if you allow all three "circled 8" symbols to be wildcards:
* From Michael Kelleher:
** thebigsecrete
Solutions that are produced via multiple operations:
* From [http://www.zodiackillerciphers.com/?p=46 Lyndon Lafferty]:
** NAME GRANT, or NAME IS GRANT
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/detailed-solution-to-z13-and-z32/ Faycal Ziraoui's solution]
A solution that applies the 408 key and interprets some symbols as nulls:
* from [http://zodiackiller.fr.yuku.com/topic/6839/Zodiacs-Name-using-408-Key Rembrandt]:
** ED SHAW
Solutions with one name part in the middle, and another name part split in half and written backwards:
* [http://www.zodiackillersite.com/viewtopic.php?p=69126#p69126 DEBBIE FARADAY]

= Other interpretations =

* "My name is" contains 8 letters. The cipher text contains 8 letters and 5 special symbols. The special symbols contain Zodiac's name and the rest just mean "My name is" (Source: Jeppesen)
* [https://www.tapatalk.com/groups/zodiackillerfr/general-book-discussion-for-hunted-the-zodiac-murd-t10141.html#p197345 "Set addition" interpretation of Z13 by Doug Oswell], resulting in solution: "FROM TED KACZYNS[K]I"
* [https://www.tapatalk.com/groups/zodiackillerfr/paul-astrup-s-theory-meteorological-symbols-challe-t10261.html#p202558 Weather symbols]
* The line after "My name is" is roughly above symbols that resemble "Tom" spelled backwards. (Source: David Cauley via YouTube comments)

Halloween card

2024-06-13T18:05:17Z

Admin: /* Cattle brands */

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Animals ===

==== Cattle Brands ====

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

==== Bird / Bat ====

The "Claude" AI gave this interpretation of the image: "This symbol appears to be a simple line drawing resembling a stylized bird or bat shape, with two angled lines forming what could be interpreted as wings, and two dots suggesting eyes."

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."
* [https://forum.zodiackillerciphers.com/community/postid/79587/ A reference to Z340's transposition scheme]

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]
* [https://www.tapatalk.com/groups/zodiackillerfr/wide-flange-beam-gaik-t2170.html "GAIK" in Brahmi alphabet]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Possible graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Catalog of sources for Zodiac's cipher symbols

2024-06-09T12:10:43Z

Admin: /* Books */

This is an attempt to track the various possible sources that people have discovered that resemble the symbols Zodiac used for his ciphers.

Note: The [[Halloween card]] has its own dedicated page.

= Astrology =

* [https://en.wikipedia.org/wiki/Astrological_symbols Astrological symbols]
* [http://zodiackillerciphers.com/images/symbols/graysmith%20astrology.jpg Astrological symbols from Graysmith's book]
* [http://zodiackillerciphers.com/images/symbols/zodiac%20alphabet.jpg "Zodiac alphabet" from "Codes and Ciphers" by John Laffin]
* [https://en.wikipedia.org/wiki/Sun_cross Sun cross]

= Crypto toys for children =

* Secret code of Junior Justice Society of America: Decoder wheel [http://zodiackillerciphers.com/images/symbols/secret%20code%20of%20junior%20justice%20society%20of%20america%201.png (Front)] [http://zodiackillerciphers.com/images/symbols/secret%20code%20of%20junior%20justice%20society%20of%20america%202.png (Back)]
* [http://zodiackillerciphers.com/images/symbols/troopers%20secret%20code.png Troopers secret code]

= Cattle brands =

* [http://zodiackillerciphers.com/images/symbols/cowboy%20code%20cattle%20brands.png Cowboy code]

= Books =

* Alchemy: [http://zodiackillerciphers.com/images/symbols/alchemy%201.png Book excerpt 1] [http://zodiackillerciphers.com/images/symbols/alchemy%202.jpeg Book excerpt 2]
** Source: [https://www.alchemywebsite.com/symbols_barlet.html Alchemical Symbols from a work by Annibal Barlet]
* Arkon Daraul, "A History of Secret Societies"
** [http://zodiackillerciphers.com/images/daraul1.jpg Book cover]
** [http://zodiackillerciphers.com/images/daraul2.jpg Cipher system resembling Zodiac's symbols]
* David Kahn, "Codebreakers"
** [https://www.reddit.com/r/ZodiacKiller/comments/1da5ou9/z_crosshair_in_codebreakers/ Porta's cipher disk image from Kahn's book]

= Other languages and alphabets =

* Greek [http://zodiackillerciphers.com/images/greekalphabet1.jpg (Alphabet)] [http://www.zodiackiller.com/MyNameIs.html (Z13 comparison)]
* [https://en.wikipedia.org/wiki/Hobo#Hobo_signs_and_graffiti Hobo signs]
* [http://zodiackillerciphers.com/images/symbols/Hippie%20Code.png "Hippie" signs]
* [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]

= Teletype =

* [http://zodiackillerciphers.com/images/teletype-zodiac.jpg Teletype keyboard arrangement 1]
* [http://zodiackillerciphers.com/images/teletype-zodiac-2.jpg Teletype keyboard arrangement 2]

= Weather symbols =

* [http://zodiackillerciphers.com/images/weather-symbols.jpg Example 1]
* [http://zodiackillerciphers.com/images/weather-symbols-3.jpg Example 2]
* [http://zodiackillerciphers.com/images/weather-symbols-4.png Example 3]

= Maps =

* [https://pubs.usgs.gov/gip/TopographicMapSymbols/topomapsymbols.pdf Topographic map symbols]
** [https://www.tapatalk.com/groups/zodiackillerfr/the-zodiac-cipher-symbols-t9872.html Detailed thread]

= Misc =

* [https://www.tapatalk.com/groups/zodiackillerfr/reddit-youtube-zodiac-nonsense-and-facebook-too-t9369-s2020.html#p232347 Fast food wrapper]

Catalog of sources for Zodiac's cipher symbols

2024-06-09T12:10:18Z

Admin: /* Books */

This is an attempt to track the various possible sources that people have discovered that resemble the symbols Zodiac used for his ciphers.

Note: The [[Halloween card]] has its own dedicated page.

= Astrology =

* [https://en.wikipedia.org/wiki/Astrological_symbols Astrological symbols]
* [http://zodiackillerciphers.com/images/symbols/graysmith%20astrology.jpg Astrological symbols from Graysmith's book]
* [http://zodiackillerciphers.com/images/symbols/zodiac%20alphabet.jpg "Zodiac alphabet" from "Codes and Ciphers" by John Laffin]
* [https://en.wikipedia.org/wiki/Sun_cross Sun cross]

= Crypto toys for children =

* Secret code of Junior Justice Society of America: Decoder wheel [http://zodiackillerciphers.com/images/symbols/secret%20code%20of%20junior%20justice%20society%20of%20america%201.png (Front)] [http://zodiackillerciphers.com/images/symbols/secret%20code%20of%20junior%20justice%20society%20of%20america%202.png (Back)]
* [http://zodiackillerciphers.com/images/symbols/troopers%20secret%20code.png Troopers secret code]

= Cattle brands =

* [http://zodiackillerciphers.com/images/symbols/cowboy%20code%20cattle%20brands.png Cowboy code]

= Books =

* Alchemy: [http://zodiackillerciphers.com/images/symbols/alchemy%201.png Book excerpt 1] [http://zodiackillerciphers.com/images/symbols/alchemy%202.jpeg Book excerpt 2]
** Source: [https://www.alchemywebsite.com/symbols_barlet.html Alchemical Symbols from a work by Annibal Barlet]
* Arkon Daraul, "A History of Secret Societies"
** [http://zodiackillerciphers.com/images/daraul1.jpg Book cover]
** [http://zodiackillerciphers.com/images/daraul2.jpg Cipher system resembling Zodiac's symbols]
** [https://www.reddit.com/r/ZodiacKiller/comments/1da5ou9/z_crosshair_in_codebreakers/ Porta's cipher disk image from Kahn's book]

= Other languages and alphabets =

* Greek [http://zodiackillerciphers.com/images/greekalphabet1.jpg (Alphabet)] [http://www.zodiackiller.com/MyNameIs.html (Z13 comparison)]
* [https://en.wikipedia.org/wiki/Hobo#Hobo_signs_and_graffiti Hobo signs]
* [http://zodiackillerciphers.com/images/symbols/Hippie%20Code.png "Hippie" signs]
* [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]

= Teletype =

* [http://zodiackillerciphers.com/images/teletype-zodiac.jpg Teletype keyboard arrangement 1]
* [http://zodiackillerciphers.com/images/teletype-zodiac-2.jpg Teletype keyboard arrangement 2]

= Weather symbols =

* [http://zodiackillerciphers.com/images/weather-symbols.jpg Example 1]
* [http://zodiackillerciphers.com/images/weather-symbols-3.jpg Example 2]
* [http://zodiackillerciphers.com/images/weather-symbols-4.png Example 3]

= Maps =

* [https://pubs.usgs.gov/gip/TopographicMapSymbols/topomapsymbols.pdf Topographic map symbols]
** [https://www.tapatalk.com/groups/zodiackillerfr/the-zodiac-cipher-symbols-t9872.html Detailed thread]

= Misc =

* [https://www.tapatalk.com/groups/zodiackillerfr/reddit-youtube-zodiac-nonsense-and-facebook-too-t9369-s2020.html#p232347 Fast food wrapper]

Encyclopedia of observations

2024-05-07T10:26:22Z

Admin: /* Unigrams */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve])

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]
* Z340's alphabet consists of 63 unique symbols. Coincidentally, the lengths of Z18, Z13, and Z32 add up to 63. (source: @rogerverreault8682 on YouTube)

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Compilation of news reports about the solution

2024-04-05T00:02:25Z

Admin: /* 8 News Now Las Vegas */

= 404 Media =
* https://www.404media.co/cryptographers-who-solved-zodiac-killer-cipher-publish-paper-about-how-they-did-it/
= 8 News Now Las Vegas =
* https://www.8newsnow.com/news/national-news/zodiac-killers-340-cipher-solved-by-private-citizens-2/

= ABC7 News Bay Area =
* https://www.youtube.com/watch?v=d64_OkthWOU
* https://abc7news.com/zodiac-cipher-sent-to-chronicle-in-1969-reportedly-solved-by-experts/8694192/
= ABC13 SF =
* https://abc13.com/8694644
= ABC Australia =
* https://www.abc.net.au/news/2020-12-12/zodiac-killer-code-cracked-by-australian-mathematician/12977342?fbclid=IwAR0HTEixB1znxsZRcmGOAmKHR9H7o9nfPx4Ms8n_cGdzZE5Mi6IP5zCaYh4
* https://www.abc.net.au/news/2020-12-12/melbourne-mathematician-cracks-zodiac-killer-cipher/12978106
* https://www.youtube.com/watch?v=8f2Z3olILxg
= ACS Information Age - AU =
* https://ia.acs.org.au/article/2020/melbourne-mathematician-cracks-zodiac-killer-s-code.html
= A&E =
* https://www.aetv.com/real-crime/zodiac-killer-messages
= The Age - AU =
* https://www.theage.com.au/world/north-america/australian-mathematician-helps-crack-zodiac-serial-killer-s-coded-message-20201212-p56mz2.html
= AlphaNews Live - Greece =
* https://www.youtube.com/watch?v=JyQPN7RNxvo
= Ars Technica =
* https://arstechnica.com/information-technology/2020/12/zodiac-killer-cipher-is-cracked-after-eluding-sleuths-for-51-years/
= BBC =
* https://www.bbc.com/news/world-us-canada-55285805
* https://www.bbc.co.uk/programmes/w172x2z2rg0q9z0 (Radio Newshour, at about 45:00)
= Big Think =
* https://bigthink.com/mind-brain/5-amazing-cracked-codes
= BoingBoing =
* https://boingboing.net/2020/12/12/the-zodiac-killers-final-cryptogram-solved.html
= CBS =
* https://www.cbsnews.com/news/zodiac-killer-cipher-solved-amateur-codebreakers-51-years/
= CBS SF =
* https://sanfrancisco.cbslocal.com/2020/12/11/zodiac-killer-cipher-cryptogram-solved-amateur-codebreakers/
* https://www.youtube.com/watch?v=tuvwCZht_EY
= Cipher Mysteries =
* http://ciphermysteries.com/2020/12/11/zodiac-z340-is-cracked
= CNA - Singapore =
* https://www.channelnewsasia.com/news/world/zodiac-killer-message-decoded-after-more-than-50-years-13755920
= CNET =
* https://www.cnet.com/news/zodiac-killer-message-known-as-340-cipher-solved-after-51-years/
= CNN =
* https://www.cnn.com/2020/12/11/us/zodiac-killer-cypher-340-code-trnd/index.html
= Daily Beast =
* https://www.thedailybeast.com/zodiac-killers-cryptogram-finally-solved-after-more-than-50-years
= Daily Mail =
* https://www.dailymail.co.uk/news/article-9044635/Zodiac-killers-1969-cipher-finally-solved-51-years-sent-San-Francisco-Chronicle.html?ito=social-twitter_dailymailus
* https://www.dailymail.co.uk/news/article-9112507/TOM-LEONARD-examines-cracked-Zodiac-killers-secret-code.html
= Daily Star =
* https://www.dailystar.co.uk/news/world-news/volunteers-crack-cryptic-zodiac-serial-23155638
= Den of Geek =
* https://www.denofgeek.com/culture/zodiac-killer-code-cracked-after-51-years/
= Discover Magazine =
* https://www.discovermagazine.com/the-sciences/how-mathematicians-cracked-the-zodiac-killers-cipher

= Distractify =
* https://www.distractify.com/p/zodiac-killer-cipher-solved
= E! =
* https://www.eonline.com/de/news/1218142/zodiac-killer-s-cipher-solved-by-code-experts-50-years-after-murders-began
* https://www.eonline.com/au/news/1218957/why-the-hunt-for-the-zodiac-killer-turned-into-a-terrifying-puzzle-for-the-ages
= FBI San Francisco =
* https://twitter.com/FBISanFrancisco/status/1337477701825925120
= Forbes =
* https://www.forbes.com/sites/nicholasreimann/2020/12/11/zodiac-killer-cipher-finally-cracked-after-51-years-and-its-as-chilling-as-youd-expect/?sh=1b0b00905ea1
= FOX5 NY =
* https://www.fox5ny.com/news/cipher-solved-in-zodiac-killer-case-decades-after-it-was-sent *
= FOX59 =
* https://fox59.com/news/zodiac-killer-mystery-code-cracked-50-years-after-murder-spree/
* https://www.youtube.com/watch?v=6E7K6FCWMCQ
= FOX KTVU SF =
* https://www.ktvu.com/news/cipher-solved-in-zodiac-killer-case-decades-after-it-was-sent
* https://www.youtube.com/watch?v=B-W4dnz5cLY
= Fox News =
* https://www.foxnews.com/us/zodiac-killer-cipher-san-francisco-newspaper
= Gizmodo =
* https://gizmodo.com/zodiac-killers-cipher-cracked-by-amateur-codebreakers-m-1845867780
= Gizmodo - AU =
* https://www.gizmodo.com.au/2020/12/zodiac-killer-cipher-solved-by-australian-mathematician/
= Global News Canada =
* https://globalnews.ca/news/7516776/zodiac-killer-cipher-solved-code
= The Guardian =
* https://www.theguardian.com/us-news/2020/dec/11/zodiac-killer-cipher-cracked-california
* https://www.theguardian.com/us-news/video/2020/dec/12/mathematician-explains-cracking-california-zodiac-killer-cipher-video
= The Hill =
* https://thehill.com/homenews/news/529929-amateur-sleuths-crack-one-of-the-zodiac-killers-ciphers-after-51-years
= IFLS =
* https://www.iflscience.com/editors-blog/zodiac-killers-infamous-340-cipher-decoded-and-his-message-finally-revealed/
= Iltalehti - FI =
* https://www.iltalehti.fi/ulkomaat/a/c3f9c605-ec41-4028-ac17-03573313c08e
= Independent =
* https://www.independent.co.uk/news/world/americas/zodiac-killer-decoded-letter-fbi-true-crime-b1770768.html
= The Infographics Show =
* https://www.youtube.com/watch?v=CX0XP3d0q2Q
= Inquisitr =
* https://www.inquisitr.com/6415526/ted-cruz-zodiac-killer-cipher-supreme-court/
= Inside Edition =
* https://www.insideedition.com/zodiac-killers-infamous-cypher-decoded-more-than-50-years-after-it-was-sent-to-journalists-63789
* https://www.insideedition.com/media/videos/zodiac-killers-340-cipher-message-decoded-by-amateur-sleuths-63800
= Interesting Engineering =
* https://interestingengineering.com/zodiac-killers-51-year-old-mystery-cipher-cracked
* https://interestingengineering.com/one-of-the-few-remaining-ciphers-has-been-solved-zodiacs-z-340-cipher
= The Irish Sun =
* https://www.thesun.ie/news/6276858/zodiac-killer-cipher-solved-melbourne-mathematician/
= Junkee =
* https://junkee.com/zodiac-killer-cypher-solved/282179
= KCBS Radio SF =
* https://www.radio.com/kcbsradio/news/local/zodiac-cipher-cracked-after-more-than-50-years
= KCRW NPR Santa Monica / Los Angeles =
* https://www.kcrw.com/news/shows/press-play-with-madeleine-brand/coronavirus-schools-epa-august-wilson-zodiac-killer/340-ciper-solved-david-oranchak
= KION Monterey CA =
* https://www.youtube.com/watch?v=mvKZvR-AMFA
= KRON4 SF =
* https://www.kron4.com/news/california/zodiac-killers-340-cipher-solved-by-private-citizens/
= LA Times =
* https://www.latimes.com/world-nation/story/2020-12-11/zodiac-cipher-solved-51-years-after-it-was-sent-to-newspaper
= Law and Crime Daily =
* https://www.youtube.com/watch?v=Usim9dp4vww
= Medium =
* https://medium.com/illumination-curated/5-lessons-from-decoding-of-zodiac-killer-340-character-ciphers-a46f37635b1a
= Mirror =
* https://www.mirror.co.uk/news/us-news/serial-killers-chilling-coded-letter-23156611
= National Cryptologic Museum Foundation =
* https://cryptologicfoundation.org/news-events/news-archive.html/article/2020/12/17/zodiac-killer-s-340-character-cipher-has-been-solved-
= National Post (Canada) =
* https://nationalpost.com/opinion/colby-cosh-decoding-the-zodiac-killer
= NBC News =
* https://www.nbcnews.com/news/us-news/i-am-not-afraid-gas-chamber-codebreakers-solve-old-zodiac-n1250948
* https://www.youtube.com/watch?v=eopl4lVQkEI (Zodiac story at 9:39)
= Nerdist =
* https://nerdist.com/article/zodiac-killers-cipher-solved-340-character-cipher/
= Newcastle Herald - AU =
* https://www.newcastleherald.com.au/story/7052382/zodiac-killer-code-cracked-after-decades/?cs=7579
= News7 Boston =
* https://whdh.com/news/codebreakers-decipher-51-year-old-note-from-zodiac-killer/
= NewsNation =
* https://www.newsnationnow.com/us-news/west/zodiac-killers-cipher-puzzle-solved-51-years-later/
= Nils Kopal =
* https://www.youtube.com/watch?v=hIrOftXgibg
= NRC - Netherlands =
* https://www.nrc.nl/nieuws/2020/12/12/gecodeerd-bericht-van-seriemoordenaar-zodiac-killer-na-ruim-50-jaar-ontcijferd-a4023615?fbclid=IwAR0OYFHmLTssnBUv090Q5myTUdrhfTUSw0lbONS9-kbnMU-MVX6ErYvt4Ys
= NTV - Russia =
* https://www.ntv.ru/novosti/2490985/
= NY Daily News =
* https://www.nydailynews.com/news/national/ny-zodiac-killer-ciper-finally-cracked-fifty-one-years-later-20201211-5mf7ujlup5dmhj64o2tnxwxbbu-story.html
= NY Post =
* https://nypost.com/2020/12/11/zodiac-killers-1969-cipher-puzzle-finally-solved/
* https://www.youtube.com/watch?v=db8O2jYI018
= NY Times =
* https://www.nytimes.com/2020/12/11/us/zodiac-killer-code-broken.html
= NZ Herald =
* https://www.nzherald.co.nz/world/california-murder-mystery-zodiac-killers-340-cipher-finally-solved-after-51-years/WF7MARG5V3YOTXLG6T66NVPDDM/
= Open Culture =
* https://www.openculture.com/?p=1084797
= People =
* https://people.com/crime/zodiac-killer-case-cipher-solved-by-codebreakers-after-51-years/
= Popular Mechanics =
* https://www.popularmechanics.com/military/aviation/a40734389/new-pop-mech-issue-secret-bomber-zodiac-killer/ (paywalled)
= Popular Science =
* https://www.popsci.com/technology/zodiac-letter-decode/

= Punjab Kesari TV - India =
* https://www.youtube.com/watch?v=5Jjk26FqGyY
= RawStory =
* https://www.rawstory.com/zodiac-killer-cypher/
= Reddit =
* https://www.reddit.com/r/UnresolvedMysteries/comments/kb8v2h/fbi_confirms_that_the_zodiac_killers_340_cypher/
* https://www.reddit.com/r/videos/comments/kb253r/the_zodiac_killers_unsolved_340_cypher_is_finally/
* https://www.reddit.com/r/serialkillers/comments/kb188w/after_51_years_the_zodiac_killers_340character/
* https://www.reddit.com/r/interestingasfuck/comments/kbne66/zodiac_killers_code_finally_broken_after_51_years/
* https://www.reddit.com/r/news/comments/kbagpv/zodiac_killers_340_cipher_sent_to_san_francisco/
* https://www.reddit.com/r/UnresolvedMysteries/comments/kfnt1f/im_kevin_fagan_san_francisco_chronicle_reporter/
= The Register =
* https://www.theregister.com/2020/12/12/zodiac_killers_cipher_solved/
* https://www.theregister.com/2024/04/04/zodiac_killer_code/

= Reuters =
* https://www.reuters.com/article/idUSKBN28M02D
= Reuters UK =
* https://uk.reuters.com/article/uk-crime-zodiac-killer-idUKKBN28L2YC
= RNZ =
* https://www.rnz.co.nz/national/programmes/morningreport/audio/2018777066/zodiac-killer-code-cracked-50-years-on
= Roanoke Times - Roanoke VA =
* https://roanoke.com/news/local/casey-roanoke-valley-scientist-helped-solve-zodiac-killer-cipher-that-stumped-experts-for-51-years/article_c9c4526c-43d7-11eb-b415-f765cf816fb5.html
= Rolling Stone =
* https://www.rollingstone.com/culture/culture-news/codebreakers-crack-zodiac-killer-unsolved-340-character-cipher-1102927/
= RTE - Ireland =
* https://www.rte.ie/news/2020/1211/1183969-zodiac-killer/
= Salon =
* https://www.salon.com/2020/12/20/zodiac-killer-code-cipher-340-sam-blake/
= Science Alert =
* https://www.sciencealert.com/team-of-amateur-code-breakers-just-solved-51-year-old-zodiac-killer-cipher
= SF Chronicle =
* https://www.sfchronicle.com/crime/article/Zodiac-340-cypher-cracked-by-code-expert-51-years-15794943.php
* https://www.sfchronicle.com/bayarea/article/Zodiac-Killer-and-the-340-Cipher-Our-15815153.php
* https://www.reddit.com/r/UnresolvedMysteries/comments/kfnt1f/im_kevin_fagan_san_francisco_chronicle_reporter/
= SF Gate =
* https://www.sfgate.com/crime/article/zodiac-340-cipher-solved-solution-code-15795178.php
* https://www.sfgate.com/sfhistory/article/why-has-Zodiac-Killer-never-been-caught-15847923.php

= Sky News =
* https://news.sky.com/story/notorious-zodiac-killers-coded-message-cracked-after-more-than-50-years-12158610
= Sydney Morning Herald - AU =
* https://www.smh.com.au/world/north-america/australian-mathematician-helps-crack-zodiac-serial-killer-s-coded-message-20201212-p56mz2.html
= The Telegraph =
* https://www.telegraph.co.uk/news/2020/12/12/zodiac-serial-killers-code-cracked-51-years/
* https://www.thetelegraph.com/insider/article/Zodiac-s-sign-language-solved-15819253.php
* https://www.telegraphindia.com/world/volunteers-crack-zodiac-san-francisco-serial-killers-cipher/cid/1800390
= ThreatPost =
* https://threatpost.com/cryptologists-zodiac-killer-340-cipher/162353/
= UNILAD =
* https://www.unilad.com/features/how-the-zodiac-killers-cryptic-code-was-deciphered-by-amateurs-20220815

= UNTV Public Service - Philippines =
* https://www.youtube.com/watch?v=RKlLW6hYG3A
= The US Sun =
* https://www.the-sun.com/news/1958492/zodiac-killer-cipher-solved-melbourne-mathematician
= USA Today =
* https://www.usatoday.com/story/news/nation/2020/12/11/zodiac-serial-killer-cipher-solved-51-years-after-coded-letter-sent/6514238002/
= US News & World Report =
* https://www.usnews.com/news/us/articles/2020-12-11/volunteer-sleuths-crack-zodiac-serial-killers-coded-message

= Vice =
* https://www.vice.com/en/article/pkd33m/hobbyist-cryptographers-seemingly-solve-infamous-zodiac-killer-cipher
* https://www.vice.com/en/article/k7a3gz/what-a-mathematician-learned-from-cracking-the-zodiac-killers-code
= Virginia Tech Engineer =
* https://eng.vt.edu/magazine//stories/spring-2020/the-new-cryptographers.html
= Wall Street Journal: Cyber Daily =
* https://www.wsj.com/articles/cyber-daily-biden-faces-early-test-on-digital-trade-with-eu-privacy-talks-suspected-russian-attack-began-with-ubiquitous-software-11608130819
= Washington Post =
* https://www.washingtonpost.com/crime-law/2020/12/11/zodiac-killer-340-cypher-solved/
= Web.de (Germany) =
* https://web.de/magazine/ratgeber/zodiac-killer-raetselhaften-codes-werk-grausamen-genies-35580324

= Wired =
* https://www.wired.com/story/zodiac-killers-cipher-finally-cracked-after-51-years/
= WISH-TV Indianapolis =
* https://www.youtube.com/watch?v=KmNIuEFiP8Y
= Wolfram =
* https://blog.wolfram.com/2021/03/24/the-solution-of-the-zodiac-killers-340-character-cipher/ (blog post written by Sam Blake)

= Yahoo =
* https://news.yahoo.com/zodiac-killer-cipher-cracked-decades-002329735.html

Compilation of news reports about the solution

2024-04-04T23:51:56Z

Admin: /* Popular Mechanics */

= 8 News Now Las Vegas =
* https://www.8newsnow.com/news/national-news/zodiac-killers-340-cipher-solved-by-private-citizens-2/
= ABC7 News Bay Area =
* https://www.youtube.com/watch?v=d64_OkthWOU
* https://abc7news.com/zodiac-cipher-sent-to-chronicle-in-1969-reportedly-solved-by-experts/8694192/
= ABC13 SF =
* https://abc13.com/8694644
= ABC Australia =
* https://www.abc.net.au/news/2020-12-12/zodiac-killer-code-cracked-by-australian-mathematician/12977342?fbclid=IwAR0HTEixB1znxsZRcmGOAmKHR9H7o9nfPx4Ms8n_cGdzZE5Mi6IP5zCaYh4
* https://www.abc.net.au/news/2020-12-12/melbourne-mathematician-cracks-zodiac-killer-cipher/12978106
* https://www.youtube.com/watch?v=8f2Z3olILxg
= ACS Information Age - AU =
* https://ia.acs.org.au/article/2020/melbourne-mathematician-cracks-zodiac-killer-s-code.html
= A&E =
* https://www.aetv.com/real-crime/zodiac-killer-messages
= The Age - AU =
* https://www.theage.com.au/world/north-america/australian-mathematician-helps-crack-zodiac-serial-killer-s-coded-message-20201212-p56mz2.html
= AlphaNews Live - Greece =
* https://www.youtube.com/watch?v=JyQPN7RNxvo
= Ars Technica =
* https://arstechnica.com/information-technology/2020/12/zodiac-killer-cipher-is-cracked-after-eluding-sleuths-for-51-years/
= BBC =
* https://www.bbc.com/news/world-us-canada-55285805
* https://www.bbc.co.uk/programmes/w172x2z2rg0q9z0 (Radio Newshour, at about 45:00)
= Big Think =
* https://bigthink.com/mind-brain/5-amazing-cracked-codes
= BoingBoing =
* https://boingboing.net/2020/12/12/the-zodiac-killers-final-cryptogram-solved.html
= CBS =
* https://www.cbsnews.com/news/zodiac-killer-cipher-solved-amateur-codebreakers-51-years/
= CBS SF =
* https://sanfrancisco.cbslocal.com/2020/12/11/zodiac-killer-cipher-cryptogram-solved-amateur-codebreakers/
* https://www.youtube.com/watch?v=tuvwCZht_EY
= Cipher Mysteries =
* http://ciphermysteries.com/2020/12/11/zodiac-z340-is-cracked
= CNA - Singapore =
* https://www.channelnewsasia.com/news/world/zodiac-killer-message-decoded-after-more-than-50-years-13755920
= CNET =
* https://www.cnet.com/news/zodiac-killer-message-known-as-340-cipher-solved-after-51-years/
= CNN =
* https://www.cnn.com/2020/12/11/us/zodiac-killer-cypher-340-code-trnd/index.html
= Daily Beast =
* https://www.thedailybeast.com/zodiac-killers-cryptogram-finally-solved-after-more-than-50-years
= Daily Mail =
* https://www.dailymail.co.uk/news/article-9044635/Zodiac-killers-1969-cipher-finally-solved-51-years-sent-San-Francisco-Chronicle.html?ito=social-twitter_dailymailus
* https://www.dailymail.co.uk/news/article-9112507/TOM-LEONARD-examines-cracked-Zodiac-killers-secret-code.html
= Daily Star =
* https://www.dailystar.co.uk/news/world-news/volunteers-crack-cryptic-zodiac-serial-23155638
= Den of Geek =
* https://www.denofgeek.com/culture/zodiac-killer-code-cracked-after-51-years/
= Discover Magazine =
* https://www.discovermagazine.com/the-sciences/how-mathematicians-cracked-the-zodiac-killers-cipher

= Distractify =
* https://www.distractify.com/p/zodiac-killer-cipher-solved
= E! =
* https://www.eonline.com/de/news/1218142/zodiac-killer-s-cipher-solved-by-code-experts-50-years-after-murders-began
* https://www.eonline.com/au/news/1218957/why-the-hunt-for-the-zodiac-killer-turned-into-a-terrifying-puzzle-for-the-ages
= FBI San Francisco =
* https://twitter.com/FBISanFrancisco/status/1337477701825925120
= Forbes =
* https://www.forbes.com/sites/nicholasreimann/2020/12/11/zodiac-killer-cipher-finally-cracked-after-51-years-and-its-as-chilling-as-youd-expect/?sh=1b0b00905ea1
= FOX5 NY =
* https://www.fox5ny.com/news/cipher-solved-in-zodiac-killer-case-decades-after-it-was-sent *
= FOX59 =
* https://fox59.com/news/zodiac-killer-mystery-code-cracked-50-years-after-murder-spree/
* https://www.youtube.com/watch?v=6E7K6FCWMCQ
= FOX KTVU SF =
* https://www.ktvu.com/news/cipher-solved-in-zodiac-killer-case-decades-after-it-was-sent
* https://www.youtube.com/watch?v=B-W4dnz5cLY
= Fox News =
* https://www.foxnews.com/us/zodiac-killer-cipher-san-francisco-newspaper
= Gizmodo =
* https://gizmodo.com/zodiac-killers-cipher-cracked-by-amateur-codebreakers-m-1845867780
= Gizmodo - AU =
* https://www.gizmodo.com.au/2020/12/zodiac-killer-cipher-solved-by-australian-mathematician/
= Global News Canada =
* https://globalnews.ca/news/7516776/zodiac-killer-cipher-solved-code
= The Guardian =
* https://www.theguardian.com/us-news/2020/dec/11/zodiac-killer-cipher-cracked-california
* https://www.theguardian.com/us-news/video/2020/dec/12/mathematician-explains-cracking-california-zodiac-killer-cipher-video
= The Hill =
* https://thehill.com/homenews/news/529929-amateur-sleuths-crack-one-of-the-zodiac-killers-ciphers-after-51-years
= IFLS =
* https://www.iflscience.com/editors-blog/zodiac-killers-infamous-340-cipher-decoded-and-his-message-finally-revealed/
= Iltalehti - FI =
* https://www.iltalehti.fi/ulkomaat/a/c3f9c605-ec41-4028-ac17-03573313c08e
= Independent =
* https://www.independent.co.uk/news/world/americas/zodiac-killer-decoded-letter-fbi-true-crime-b1770768.html
= The Infographics Show =
* https://www.youtube.com/watch?v=CX0XP3d0q2Q
= Inquisitr =
* https://www.inquisitr.com/6415526/ted-cruz-zodiac-killer-cipher-supreme-court/
= Inside Edition =
* https://www.insideedition.com/zodiac-killers-infamous-cypher-decoded-more-than-50-years-after-it-was-sent-to-journalists-63789
* https://www.insideedition.com/media/videos/zodiac-killers-340-cipher-message-decoded-by-amateur-sleuths-63800
= Interesting Engineering =
* https://interestingengineering.com/zodiac-killers-51-year-old-mystery-cipher-cracked
* https://interestingengineering.com/one-of-the-few-remaining-ciphers-has-been-solved-zodiacs-z-340-cipher
= The Irish Sun =
* https://www.thesun.ie/news/6276858/zodiac-killer-cipher-solved-melbourne-mathematician/
= Junkee =
* https://junkee.com/zodiac-killer-cypher-solved/282179
= KCBS Radio SF =
* https://www.radio.com/kcbsradio/news/local/zodiac-cipher-cracked-after-more-than-50-years
= KCRW NPR Santa Monica / Los Angeles =
* https://www.kcrw.com/news/shows/press-play-with-madeleine-brand/coronavirus-schools-epa-august-wilson-zodiac-killer/340-ciper-solved-david-oranchak
= KION Monterey CA =
* https://www.youtube.com/watch?v=mvKZvR-AMFA
= KRON4 SF =
* https://www.kron4.com/news/california/zodiac-killers-340-cipher-solved-by-private-citizens/
= LA Times =
* https://www.latimes.com/world-nation/story/2020-12-11/zodiac-cipher-solved-51-years-after-it-was-sent-to-newspaper
= Law and Crime Daily =
* https://www.youtube.com/watch?v=Usim9dp4vww
= Medium =
* https://medium.com/illumination-curated/5-lessons-from-decoding-of-zodiac-killer-340-character-ciphers-a46f37635b1a
= Mirror =
* https://www.mirror.co.uk/news/us-news/serial-killers-chilling-coded-letter-23156611
= National Cryptologic Museum Foundation =
* https://cryptologicfoundation.org/news-events/news-archive.html/article/2020/12/17/zodiac-killer-s-340-character-cipher-has-been-solved-
= National Post (Canada) =
* https://nationalpost.com/opinion/colby-cosh-decoding-the-zodiac-killer
= NBC News =
* https://www.nbcnews.com/news/us-news/i-am-not-afraid-gas-chamber-codebreakers-solve-old-zodiac-n1250948
* https://www.youtube.com/watch?v=eopl4lVQkEI (Zodiac story at 9:39)
= Nerdist =
* https://nerdist.com/article/zodiac-killers-cipher-solved-340-character-cipher/
= Newcastle Herald - AU =
* https://www.newcastleherald.com.au/story/7052382/zodiac-killer-code-cracked-after-decades/?cs=7579
= News7 Boston =
* https://whdh.com/news/codebreakers-decipher-51-year-old-note-from-zodiac-killer/
= NewsNation =
* https://www.newsnationnow.com/us-news/west/zodiac-killers-cipher-puzzle-solved-51-years-later/
= Nils Kopal =
* https://www.youtube.com/watch?v=hIrOftXgibg
= NRC - Netherlands =
* https://www.nrc.nl/nieuws/2020/12/12/gecodeerd-bericht-van-seriemoordenaar-zodiac-killer-na-ruim-50-jaar-ontcijferd-a4023615?fbclid=IwAR0OYFHmLTssnBUv090Q5myTUdrhfTUSw0lbONS9-kbnMU-MVX6ErYvt4Ys
= NTV - Russia =
* https://www.ntv.ru/novosti/2490985/
= NY Daily News =
* https://www.nydailynews.com/news/national/ny-zodiac-killer-ciper-finally-cracked-fifty-one-years-later-20201211-5mf7ujlup5dmhj64o2tnxwxbbu-story.html
= NY Post =
* https://nypost.com/2020/12/11/zodiac-killers-1969-cipher-puzzle-finally-solved/
* https://www.youtube.com/watch?v=db8O2jYI018
= NY Times =
* https://www.nytimes.com/2020/12/11/us/zodiac-killer-code-broken.html
= NZ Herald =
* https://www.nzherald.co.nz/world/california-murder-mystery-zodiac-killers-340-cipher-finally-solved-after-51-years/WF7MARG5V3YOTXLG6T66NVPDDM/
= Open Culture =
* https://www.openculture.com/?p=1084797
= People =
* https://people.com/crime/zodiac-killer-case-cipher-solved-by-codebreakers-after-51-years/
= Popular Mechanics =
* https://www.popularmechanics.com/military/aviation/a40734389/new-pop-mech-issue-secret-bomber-zodiac-killer/ (paywalled)
= Popular Science =
* https://www.popsci.com/technology/zodiac-letter-decode/

= Punjab Kesari TV - India =
* https://www.youtube.com/watch?v=5Jjk26FqGyY
= RawStory =
* https://www.rawstory.com/zodiac-killer-cypher/
= Reddit =
* https://www.reddit.com/r/UnresolvedMysteries/comments/kb8v2h/fbi_confirms_that_the_zodiac_killers_340_cypher/
* https://www.reddit.com/r/videos/comments/kb253r/the_zodiac_killers_unsolved_340_cypher_is_finally/
* https://www.reddit.com/r/serialkillers/comments/kb188w/after_51_years_the_zodiac_killers_340character/
* https://www.reddit.com/r/interestingasfuck/comments/kbne66/zodiac_killers_code_finally_broken_after_51_years/
* https://www.reddit.com/r/news/comments/kbagpv/zodiac_killers_340_cipher_sent_to_san_francisco/
* https://www.reddit.com/r/UnresolvedMysteries/comments/kfnt1f/im_kevin_fagan_san_francisco_chronicle_reporter/
= The Register =
* https://www.theregister.com/2020/12/12/zodiac_killers_cipher_solved/
* https://www.theregister.com/2024/04/04/zodiac_killer_code/

= Reuters =
* https://www.reuters.com/article/idUSKBN28M02D
= Reuters UK =
* https://uk.reuters.com/article/uk-crime-zodiac-killer-idUKKBN28L2YC
= RNZ =
* https://www.rnz.co.nz/national/programmes/morningreport/audio/2018777066/zodiac-killer-code-cracked-50-years-on
= Roanoke Times - Roanoke VA =
* https://roanoke.com/news/local/casey-roanoke-valley-scientist-helped-solve-zodiac-killer-cipher-that-stumped-experts-for-51-years/article_c9c4526c-43d7-11eb-b415-f765cf816fb5.html
= Rolling Stone =
* https://www.rollingstone.com/culture/culture-news/codebreakers-crack-zodiac-killer-unsolved-340-character-cipher-1102927/
= RTE - Ireland =
* https://www.rte.ie/news/2020/1211/1183969-zodiac-killer/
= Salon =
* https://www.salon.com/2020/12/20/zodiac-killer-code-cipher-340-sam-blake/
= Science Alert =
* https://www.sciencealert.com/team-of-amateur-code-breakers-just-solved-51-year-old-zodiac-killer-cipher
= SF Chronicle =
* https://www.sfchronicle.com/crime/article/Zodiac-340-cypher-cracked-by-code-expert-51-years-15794943.php
* https://www.sfchronicle.com/bayarea/article/Zodiac-Killer-and-the-340-Cipher-Our-15815153.php
* https://www.reddit.com/r/UnresolvedMysteries/comments/kfnt1f/im_kevin_fagan_san_francisco_chronicle_reporter/
= SF Gate =
* https://www.sfgate.com/crime/article/zodiac-340-cipher-solved-solution-code-15795178.php
* https://www.sfgate.com/sfhistory/article/why-has-Zodiac-Killer-never-been-caught-15847923.php

= Sky News =
* https://news.sky.com/story/notorious-zodiac-killers-coded-message-cracked-after-more-than-50-years-12158610
= Sydney Morning Herald - AU =
* https://www.smh.com.au/world/north-america/australian-mathematician-helps-crack-zodiac-serial-killer-s-coded-message-20201212-p56mz2.html
= The Telegraph =
* https://www.telegraph.co.uk/news/2020/12/12/zodiac-serial-killers-code-cracked-51-years/
* https://www.thetelegraph.com/insider/article/Zodiac-s-sign-language-solved-15819253.php
* https://www.telegraphindia.com/world/volunteers-crack-zodiac-san-francisco-serial-killers-cipher/cid/1800390
= ThreatPost =
* https://threatpost.com/cryptologists-zodiac-killer-340-cipher/162353/
= UNILAD =
* https://www.unilad.com/features/how-the-zodiac-killers-cryptic-code-was-deciphered-by-amateurs-20220815

= UNTV Public Service - Philippines =
* https://www.youtube.com/watch?v=RKlLW6hYG3A
= The US Sun =
* https://www.the-sun.com/news/1958492/zodiac-killer-cipher-solved-melbourne-mathematician
= USA Today =
* https://www.usatoday.com/story/news/nation/2020/12/11/zodiac-serial-killer-cipher-solved-51-years-after-coded-letter-sent/6514238002/
= US News & World Report =
* https://www.usnews.com/news/us/articles/2020-12-11/volunteer-sleuths-crack-zodiac-serial-killers-coded-message

= Vice =
* https://www.vice.com/en/article/pkd33m/hobbyist-cryptographers-seemingly-solve-infamous-zodiac-killer-cipher
* https://www.vice.com/en/article/k7a3gz/what-a-mathematician-learned-from-cracking-the-zodiac-killers-code
= Virginia Tech Engineer =
* https://eng.vt.edu/magazine//stories/spring-2020/the-new-cryptographers.html
= Wall Street Journal: Cyber Daily =
* https://www.wsj.com/articles/cyber-daily-biden-faces-early-test-on-digital-trade-with-eu-privacy-talks-suspected-russian-attack-began-with-ubiquitous-software-11608130819
= Washington Post =
* https://www.washingtonpost.com/crime-law/2020/12/11/zodiac-killer-340-cypher-solved/
= Web.de (Germany) =
* https://web.de/magazine/ratgeber/zodiac-killer-raetselhaften-codes-werk-grausamen-genies-35580324

= Wired =
* https://www.wired.com/story/zodiac-killers-cipher-finally-cracked-after-51-years/
= WISH-TV Indianapolis =
* https://www.youtube.com/watch?v=KmNIuEFiP8Y
= Wolfram =
* https://blog.wolfram.com/2021/03/24/the-solution-of-the-zodiac-killers-340-character-cipher/ (blog post written by Sam Blake)

= Yahoo =
* https://news.yahoo.com/zodiac-killer-cipher-cracked-decades-002329735.html

Compilation of news reports about the solution

2024-04-04T23:51:27Z

Admin: /* The Register */

= 8 News Now Las Vegas =
* https://www.8newsnow.com/news/national-news/zodiac-killers-340-cipher-solved-by-private-citizens-2/
= ABC7 News Bay Area =
* https://www.youtube.com/watch?v=d64_OkthWOU
* https://abc7news.com/zodiac-cipher-sent-to-chronicle-in-1969-reportedly-solved-by-experts/8694192/
= ABC13 SF =
* https://abc13.com/8694644
= ABC Australia =
* https://www.abc.net.au/news/2020-12-12/zodiac-killer-code-cracked-by-australian-mathematician/12977342?fbclid=IwAR0HTEixB1znxsZRcmGOAmKHR9H7o9nfPx4Ms8n_cGdzZE5Mi6IP5zCaYh4
* https://www.abc.net.au/news/2020-12-12/melbourne-mathematician-cracks-zodiac-killer-cipher/12978106
* https://www.youtube.com/watch?v=8f2Z3olILxg
= ACS Information Age - AU =
* https://ia.acs.org.au/article/2020/melbourne-mathematician-cracks-zodiac-killer-s-code.html
= A&E =
* https://www.aetv.com/real-crime/zodiac-killer-messages
= The Age - AU =
* https://www.theage.com.au/world/north-america/australian-mathematician-helps-crack-zodiac-serial-killer-s-coded-message-20201212-p56mz2.html
= AlphaNews Live - Greece =
* https://www.youtube.com/watch?v=JyQPN7RNxvo
= Ars Technica =
* https://arstechnica.com/information-technology/2020/12/zodiac-killer-cipher-is-cracked-after-eluding-sleuths-for-51-years/
= BBC =
* https://www.bbc.com/news/world-us-canada-55285805
* https://www.bbc.co.uk/programmes/w172x2z2rg0q9z0 (Radio Newshour, at about 45:00)
= Big Think =
* https://bigthink.com/mind-brain/5-amazing-cracked-codes
= BoingBoing =
* https://boingboing.net/2020/12/12/the-zodiac-killers-final-cryptogram-solved.html
= CBS =
* https://www.cbsnews.com/news/zodiac-killer-cipher-solved-amateur-codebreakers-51-years/
= CBS SF =
* https://sanfrancisco.cbslocal.com/2020/12/11/zodiac-killer-cipher-cryptogram-solved-amateur-codebreakers/
* https://www.youtube.com/watch?v=tuvwCZht_EY
= Cipher Mysteries =
* http://ciphermysteries.com/2020/12/11/zodiac-z340-is-cracked
= CNA - Singapore =
* https://www.channelnewsasia.com/news/world/zodiac-killer-message-decoded-after-more-than-50-years-13755920
= CNET =
* https://www.cnet.com/news/zodiac-killer-message-known-as-340-cipher-solved-after-51-years/
= CNN =
* https://www.cnn.com/2020/12/11/us/zodiac-killer-cypher-340-code-trnd/index.html
= Daily Beast =
* https://www.thedailybeast.com/zodiac-killers-cryptogram-finally-solved-after-more-than-50-years
= Daily Mail =
* https://www.dailymail.co.uk/news/article-9044635/Zodiac-killers-1969-cipher-finally-solved-51-years-sent-San-Francisco-Chronicle.html?ito=social-twitter_dailymailus
* https://www.dailymail.co.uk/news/article-9112507/TOM-LEONARD-examines-cracked-Zodiac-killers-secret-code.html
= Daily Star =
* https://www.dailystar.co.uk/news/world-news/volunteers-crack-cryptic-zodiac-serial-23155638
= Den of Geek =
* https://www.denofgeek.com/culture/zodiac-killer-code-cracked-after-51-years/
= Discover Magazine =
* https://www.discovermagazine.com/the-sciences/how-mathematicians-cracked-the-zodiac-killers-cipher

= Distractify =
* https://www.distractify.com/p/zodiac-killer-cipher-solved
= E! =
* https://www.eonline.com/de/news/1218142/zodiac-killer-s-cipher-solved-by-code-experts-50-years-after-murders-began
* https://www.eonline.com/au/news/1218957/why-the-hunt-for-the-zodiac-killer-turned-into-a-terrifying-puzzle-for-the-ages
= FBI San Francisco =
* https://twitter.com/FBISanFrancisco/status/1337477701825925120
= Forbes =
* https://www.forbes.com/sites/nicholasreimann/2020/12/11/zodiac-killer-cipher-finally-cracked-after-51-years-and-its-as-chilling-as-youd-expect/?sh=1b0b00905ea1
= FOX5 NY =
* https://www.fox5ny.com/news/cipher-solved-in-zodiac-killer-case-decades-after-it-was-sent *
= FOX59 =
* https://fox59.com/news/zodiac-killer-mystery-code-cracked-50-years-after-murder-spree/
* https://www.youtube.com/watch?v=6E7K6FCWMCQ
= FOX KTVU SF =
* https://www.ktvu.com/news/cipher-solved-in-zodiac-killer-case-decades-after-it-was-sent
* https://www.youtube.com/watch?v=B-W4dnz5cLY
= Fox News =
* https://www.foxnews.com/us/zodiac-killer-cipher-san-francisco-newspaper
= Gizmodo =
* https://gizmodo.com/zodiac-killers-cipher-cracked-by-amateur-codebreakers-m-1845867780
= Gizmodo - AU =
* https://www.gizmodo.com.au/2020/12/zodiac-killer-cipher-solved-by-australian-mathematician/
= Global News Canada =
* https://globalnews.ca/news/7516776/zodiac-killer-cipher-solved-code
= The Guardian =
* https://www.theguardian.com/us-news/2020/dec/11/zodiac-killer-cipher-cracked-california
* https://www.theguardian.com/us-news/video/2020/dec/12/mathematician-explains-cracking-california-zodiac-killer-cipher-video
= The Hill =
* https://thehill.com/homenews/news/529929-amateur-sleuths-crack-one-of-the-zodiac-killers-ciphers-after-51-years
= IFLS =
* https://www.iflscience.com/editors-blog/zodiac-killers-infamous-340-cipher-decoded-and-his-message-finally-revealed/
= Iltalehti - FI =
* https://www.iltalehti.fi/ulkomaat/a/c3f9c605-ec41-4028-ac17-03573313c08e
= Independent =
* https://www.independent.co.uk/news/world/americas/zodiac-killer-decoded-letter-fbi-true-crime-b1770768.html
= The Infographics Show =
* https://www.youtube.com/watch?v=CX0XP3d0q2Q
= Inquisitr =
* https://www.inquisitr.com/6415526/ted-cruz-zodiac-killer-cipher-supreme-court/
= Inside Edition =
* https://www.insideedition.com/zodiac-killers-infamous-cypher-decoded-more-than-50-years-after-it-was-sent-to-journalists-63789
* https://www.insideedition.com/media/videos/zodiac-killers-340-cipher-message-decoded-by-amateur-sleuths-63800
= Interesting Engineering =
* https://interestingengineering.com/zodiac-killers-51-year-old-mystery-cipher-cracked
* https://interestingengineering.com/one-of-the-few-remaining-ciphers-has-been-solved-zodiacs-z-340-cipher
= The Irish Sun =
* https://www.thesun.ie/news/6276858/zodiac-killer-cipher-solved-melbourne-mathematician/
= Junkee =
* https://junkee.com/zodiac-killer-cypher-solved/282179
= KCBS Radio SF =
* https://www.radio.com/kcbsradio/news/local/zodiac-cipher-cracked-after-more-than-50-years
= KCRW NPR Santa Monica / Los Angeles =
* https://www.kcrw.com/news/shows/press-play-with-madeleine-brand/coronavirus-schools-epa-august-wilson-zodiac-killer/340-ciper-solved-david-oranchak
= KION Monterey CA =
* https://www.youtube.com/watch?v=mvKZvR-AMFA
= KRON4 SF =
* https://www.kron4.com/news/california/zodiac-killers-340-cipher-solved-by-private-citizens/
= LA Times =
* https://www.latimes.com/world-nation/story/2020-12-11/zodiac-cipher-solved-51-years-after-it-was-sent-to-newspaper
= Law and Crime Daily =
* https://www.youtube.com/watch?v=Usim9dp4vww
= Medium =
* https://medium.com/illumination-curated/5-lessons-from-decoding-of-zodiac-killer-340-character-ciphers-a46f37635b1a
= Mirror =
* https://www.mirror.co.uk/news/us-news/serial-killers-chilling-coded-letter-23156611
= National Cryptologic Museum Foundation =
* https://cryptologicfoundation.org/news-events/news-archive.html/article/2020/12/17/zodiac-killer-s-340-character-cipher-has-been-solved-
= National Post (Canada) =
* https://nationalpost.com/opinion/colby-cosh-decoding-the-zodiac-killer
= NBC News =
* https://www.nbcnews.com/news/us-news/i-am-not-afraid-gas-chamber-codebreakers-solve-old-zodiac-n1250948
* https://www.youtube.com/watch?v=eopl4lVQkEI (Zodiac story at 9:39)
= Nerdist =
* https://nerdist.com/article/zodiac-killers-cipher-solved-340-character-cipher/
= Newcastle Herald - AU =
* https://www.newcastleherald.com.au/story/7052382/zodiac-killer-code-cracked-after-decades/?cs=7579
= News7 Boston =
* https://whdh.com/news/codebreakers-decipher-51-year-old-note-from-zodiac-killer/
= NewsNation =
* https://www.newsnationnow.com/us-news/west/zodiac-killers-cipher-puzzle-solved-51-years-later/
= Nils Kopal =
* https://www.youtube.com/watch?v=hIrOftXgibg
= NRC - Netherlands =
* https://www.nrc.nl/nieuws/2020/12/12/gecodeerd-bericht-van-seriemoordenaar-zodiac-killer-na-ruim-50-jaar-ontcijferd-a4023615?fbclid=IwAR0OYFHmLTssnBUv090Q5myTUdrhfTUSw0lbONS9-kbnMU-MVX6ErYvt4Ys
= NTV - Russia =
* https://www.ntv.ru/novosti/2490985/
= NY Daily News =
* https://www.nydailynews.com/news/national/ny-zodiac-killer-ciper-finally-cracked-fifty-one-years-later-20201211-5mf7ujlup5dmhj64o2tnxwxbbu-story.html
= NY Post =
* https://nypost.com/2020/12/11/zodiac-killers-1969-cipher-puzzle-finally-solved/
* https://www.youtube.com/watch?v=db8O2jYI018
= NY Times =
* https://www.nytimes.com/2020/12/11/us/zodiac-killer-code-broken.html
= NZ Herald =
* https://www.nzherald.co.nz/world/california-murder-mystery-zodiac-killers-340-cipher-finally-solved-after-51-years/WF7MARG5V3YOTXLG6T66NVPDDM/
= Open Culture =
* https://www.openculture.com/?p=1084797
= People =
* https://people.com/crime/zodiac-killer-case-cipher-solved-by-codebreakers-after-51-years/
= Popular Mechanics =
* https://www.popularmechanics.com/military/aviation/a40734389/new-pop-mech-issue-secret-bomber-zodiac-killer/ (paywalled)

= Punjab Kesari TV - India =
* https://www.youtube.com/watch?v=5Jjk26FqGyY
= RawStory =
* https://www.rawstory.com/zodiac-killer-cypher/
= Reddit =
* https://www.reddit.com/r/UnresolvedMysteries/comments/kb8v2h/fbi_confirms_that_the_zodiac_killers_340_cypher/
* https://www.reddit.com/r/videos/comments/kb253r/the_zodiac_killers_unsolved_340_cypher_is_finally/
* https://www.reddit.com/r/serialkillers/comments/kb188w/after_51_years_the_zodiac_killers_340character/
* https://www.reddit.com/r/interestingasfuck/comments/kbne66/zodiac_killers_code_finally_broken_after_51_years/
* https://www.reddit.com/r/news/comments/kbagpv/zodiac_killers_340_cipher_sent_to_san_francisco/
* https://www.reddit.com/r/UnresolvedMysteries/comments/kfnt1f/im_kevin_fagan_san_francisco_chronicle_reporter/
= The Register =
* https://www.theregister.com/2020/12/12/zodiac_killers_cipher_solved/
* https://www.theregister.com/2024/04/04/zodiac_killer_code/

= Reuters =
* https://www.reuters.com/article/idUSKBN28M02D
= Reuters UK =
* https://uk.reuters.com/article/uk-crime-zodiac-killer-idUKKBN28L2YC
= RNZ =
* https://www.rnz.co.nz/national/programmes/morningreport/audio/2018777066/zodiac-killer-code-cracked-50-years-on
= Roanoke Times - Roanoke VA =
* https://roanoke.com/news/local/casey-roanoke-valley-scientist-helped-solve-zodiac-killer-cipher-that-stumped-experts-for-51-years/article_c9c4526c-43d7-11eb-b415-f765cf816fb5.html
= Rolling Stone =
* https://www.rollingstone.com/culture/culture-news/codebreakers-crack-zodiac-killer-unsolved-340-character-cipher-1102927/
= RTE - Ireland =
* https://www.rte.ie/news/2020/1211/1183969-zodiac-killer/
= Salon =
* https://www.salon.com/2020/12/20/zodiac-killer-code-cipher-340-sam-blake/
= Science Alert =
* https://www.sciencealert.com/team-of-amateur-code-breakers-just-solved-51-year-old-zodiac-killer-cipher
= SF Chronicle =
* https://www.sfchronicle.com/crime/article/Zodiac-340-cypher-cracked-by-code-expert-51-years-15794943.php
* https://www.sfchronicle.com/bayarea/article/Zodiac-Killer-and-the-340-Cipher-Our-15815153.php
* https://www.reddit.com/r/UnresolvedMysteries/comments/kfnt1f/im_kevin_fagan_san_francisco_chronicle_reporter/
= SF Gate =
* https://www.sfgate.com/crime/article/zodiac-340-cipher-solved-solution-code-15795178.php
* https://www.sfgate.com/sfhistory/article/why-has-Zodiac-Killer-never-been-caught-15847923.php

= Sky News =
* https://news.sky.com/story/notorious-zodiac-killers-coded-message-cracked-after-more-than-50-years-12158610
= Sydney Morning Herald - AU =
* https://www.smh.com.au/world/north-america/australian-mathematician-helps-crack-zodiac-serial-killer-s-coded-message-20201212-p56mz2.html
= The Telegraph =
* https://www.telegraph.co.uk/news/2020/12/12/zodiac-serial-killers-code-cracked-51-years/
* https://www.thetelegraph.com/insider/article/Zodiac-s-sign-language-solved-15819253.php
* https://www.telegraphindia.com/world/volunteers-crack-zodiac-san-francisco-serial-killers-cipher/cid/1800390
= ThreatPost =
* https://threatpost.com/cryptologists-zodiac-killer-340-cipher/162353/
= UNILAD =
* https://www.unilad.com/features/how-the-zodiac-killers-cryptic-code-was-deciphered-by-amateurs-20220815

= UNTV Public Service - Philippines =
* https://www.youtube.com/watch?v=RKlLW6hYG3A
= The US Sun =
* https://www.the-sun.com/news/1958492/zodiac-killer-cipher-solved-melbourne-mathematician
= USA Today =
* https://www.usatoday.com/story/news/nation/2020/12/11/zodiac-serial-killer-cipher-solved-51-years-after-coded-letter-sent/6514238002/
= US News & World Report =
* https://www.usnews.com/news/us/articles/2020-12-11/volunteer-sleuths-crack-zodiac-serial-killers-coded-message

= Vice =
* https://www.vice.com/en/article/pkd33m/hobbyist-cryptographers-seemingly-solve-infamous-zodiac-killer-cipher
* https://www.vice.com/en/article/k7a3gz/what-a-mathematician-learned-from-cracking-the-zodiac-killers-code
= Virginia Tech Engineer =
* https://eng.vt.edu/magazine//stories/spring-2020/the-new-cryptographers.html
= Wall Street Journal: Cyber Daily =
* https://www.wsj.com/articles/cyber-daily-biden-faces-early-test-on-digital-trade-with-eu-privacy-talks-suspected-russian-attack-began-with-ubiquitous-software-11608130819
= Washington Post =
* https://www.washingtonpost.com/crime-law/2020/12/11/zodiac-killer-340-cypher-solved/
= Web.de (Germany) =
* https://web.de/magazine/ratgeber/zodiac-killer-raetselhaften-codes-werk-grausamen-genies-35580324

= Wired =
* https://www.wired.com/story/zodiac-killers-cipher-finally-cracked-after-51-years/
= WISH-TV Indianapolis =
* https://www.youtube.com/watch?v=KmNIuEFiP8Y
= Wolfram =
* https://blog.wolfram.com/2021/03/24/the-solution-of-the-zodiac-killers-340-character-cipher/ (blog post written by Sam Blake)

= Yahoo =
* https://news.yahoo.com/zodiac-killer-cipher-cracked-decades-002329735.html

Z13 Solutions

2024-02-06T12:00:55Z

Admin: /* Partial solution from "granny101" */

= Solutions that fit the ciphertext as is =

This section only shows proposed solutions that fit the cipher text "as is". No anagramming or other re-arrangements are used here, and the cipher is considered to be strictly a substitution cipher. Solutions that permit anagramming are very easy to come by, as there are several billion possible string combinations to choose from. Solutions that do not require anagramming are still numerous, however, which increases the difficulty of knowing which one is correct.

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=50&t=1390&p=24191#p24190 "Quill"] ==
* Eddie Penerden
* Stan T E Case (using "8"s as spaces)
* Greg N A Vega (using "8"s as spaces)

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5677 "glurk"] (homophonic solutions) ==
* Steve Pete West
* Adrian a Harrah
* Shannon E Nease
* Steve Pete Best
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Eddie Gene Oden
* Steve Pete Vest
* Barney E Yearby
* Gene Lyle Lange
* Eddie Gene Eden
* Ed Steven Eisen
* E Alva Vanallen
* Angelo Lyle Gay
* Eddie Rene Oden
* Isreal a Sarris
* Carl Bob Abarca
* Elliot O Roller
* Andre Reyes Day
* Ed Steve Nelsen
* Shane Pete East
* Lee Gene Levell
* Eddie Rene Eden
* Rueben E Segers
* Rueben E Severs
* Eddie Gene Aden
* Eddie Dewey Dew
* Shane Pete Mast
* Ed Steve Reeser
* Ed Steve Reiser
* Lee Rene Levell
* Neal Alan Amann
* Sean Lyle Lease
* Otto Alan Alton
* Otto Alan Acton
* Otto Alan Aston
* Otto Alan Anton
* Eddie Rene Aden
* Lee Jamal Abell
* Andre Gene Adan
* Reed Alan Ahern
* Shane Pete Fast
* Elliot O Yokley
* Elliot O Soules
* Lee Pete Levell
* Ira Lamar Adair
* Neil Lyle Laine
* Teodoro Tom Ott
* Otto Adam Altom
* Noah Alan Amann
* Eddy Alan Alden
* Lee Jewel Ezell
* Cory Bob Abarca
* Andre Rene Adan
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Earle Gene Wren
* Dean Rory Ready
* Dana Bob Obando
* Luis Rory Reily
* Otto Asa Santos
* Eric Asa Rapier
* Gino Lyle Lange
* Eddy Alan Arden
* Kent Lyle Linke
* Andre Dewey Daw
* Eddie Les Eades
* Louie Pete Ault
* Eddie Jewel Dew
* Ian Reyes Ennis
* Edison O Rosier
* Ollie Lee Enloe
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Ira Jamar Adair
* Earle Rene Wren
* Ernie Dewey New
* Lee Jewel Ewell
* Eddie Wes Eades
* Drew Rory Reedy
* Al Isaias Arias
* Ollie Derek Lor
* Cary Bob Abarca
* Emile Gene Lien
* Arlie Dewey Law
* Ollie Dewey Low
* Rob Dewey Embry
* Curt Bob Abarca
* Earl Asa Laurel
* Stefan Asa Hess
* Eddie Reyes Dey
* Eli Dana Rapier
* Dane Bob Obando
* Elmo Rory Ramey
* Lee Jere Levell
* Ali Rufus Urias
* Emile Rene Lien
* Eddie Jere Eder
* Stan Lyle Lease
* Chi Derek Edick
* Earle Gene Oren
* Emile Gene Bien
* Earle Gene Uren
* Arturo Rory Tao
* Otis Asa Nation
* Genaro Rory Ngo
* Dane Lyle Linde
* Dane Lyle Lynde
* Dane Lyle Lunde
* Scot Lyle Loose
* Ali Reyes Elias
* Art Solomon Tam
* Donn Bob Obando
* Dino Bob Obando
* Andre Jewel Daw
* Neal Adan Amann
* Emile Rene Bien
* Otto Adan Alton
* Earle Rene Uren
* Otto Adan Acton
* Earle Rene Oren
* Otto Adan Anton
* Otto Adan Aston
* Dallas Asa Olds
* Erik Asa Rapier
* Reed Adan Ahern
* Ernie Jewel New
* Donn Lyle Linde
* Dino Lyle Linde
* Donn Lyle Lynde
* Dino Lyle Lunde
* Donn Lyle Lunde
* Dino Lyle Lynde
* Dong Bob Obando
* Teodoro Tod Ott
* Stefan Asa Bess
* Noah Adan Amann
* Arlie Jewel Law
* Issac Jc Ocasio
* Arlie Reyes Lay
* Ed Teodoro Ater
* Ollie Jewel Low
* Eddy Adan Alden
* Shad Lyle Lease
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Shon Lyle Loose
* Dong Lyle Lunde
* Ollie Reyes Loy
* Stefan Asa Ness
* Earle Dewey Rew
* Reed Asa Sayers
* Anibal Asa Dias
* Noe Reyes Edens
* Delmar Asa Olds
* Isreal Al Abril
* Isreal Al April
* Earle Reyes Rey
* Ernie Les Eanes
* Eddy Adan Arden
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Ernie Reyes Ney
* Morgan Asa Arms
* Olin Asa Nation
* Lou Solomon Ulm
* Ernie Wes Eanes
* Ernie Rey Edney
* Odis Asa Nation
* Murray Asa Arms
* Noe Reyes Evens
* Ollie Dee Enloe
* Leif Rory Reily
* Elmo Asa Raymer
* Isaiah Asa Sais
* Anibal Asa Bias
* Ollie Jere Flor
* Reed Asa Sagers
* Reed Asa Sauers
* Stefan Asa Vess
* Stefan Asa Jess
* Stefan Asa Gess
* Ezra Asa Laurel
* Erin Asa Rapier
* Emile Jere Mier
* Emile Jere Pier
* Emile Jere Bier
* Earle Jewel Rew
* Emile Jere Wier
* Emile Jere Kier
* Anibal Asa Sias
* Isaias Asa Sais
* Paris Asa Serpa
* Arlie Jere Klar
* Luigi Gil Ifill
* Hai Solomon Ihm
* Darell L Ilardi
* Chi Derek Emick
* Eddie Lee Emdee
* Daryl Al Ilardi
* Arlie Rey Emlay
* Eddie Rene Iden
* Chi Derek Enick
* Earle Rene Hren
* Trevor O Howeth
* Earle Gene Hren
* Duncan Asa Ends
* Danial Asa Ends
* Louie Pete Hult
* Eddie Gene Iden
* Chas Asa Kasack
* Clay Asa Kasack
* Lee Jewel Euell
* Chad Asa Kasack
* Ian Dana Katnik
* Chet Asa Kazeck
* Shane Pete Kast
* Leo Jewel Etoll
* Ian Dana Kamnik
* M Keenan Ingemi
* M Vernon Ingemi
* Ernie Jere Iner
* Eddie Dee Emdee
* Isaias Asa Kais
* Ed Steven Elsen
* Steve Pete Jest
* Isaiah Asa Kais
* Theron O Howeth
* Neil Asa Garing
* Ernie Wes Ennes
* Noah Asa Galang
* Shane Leo Eraso
* Steve Pete Gest
* Emile Jere Gier
* Israel E Gehrig
* N Eugene Genung
* Neal Asa Galang
* Elijah Asa Fies
* Steve Pete Fest
* Eli Peter Etier
* Ed Steven Essen
* Stefan Asa Fess
* Chi Derek Erick
* Ollie Pete Flot
* Earle Pete Fret
* Ernie Ben Ennen
* Emile Jere Hier
* Ernie Len Ennen
* Ernie Ken Ennen
* Theron O Horeth
* Trevor O Horeth
* Lee Bo Holowell
* Chi Derek Evick
* Ernie Les Ennes
* Adrian Asa Gras
* Earle Gene Gren
* Noe Reyes Ewens
* Ollie Jere Glor
* Shad Asa Habash
* Stan Asa Habash
* Earle Rene Gren
* Sean Asa Habash
* Aldo Alan Ardan
* Andy Adan Ardan
* Art Jamal Antal
* Aldo Adan Ardan
* Eli Jamal Ariel
* Elijah Al Ariel
* Andy Alan Ardan
* Dorian Asa Ards
* Leland N Analla
* R Keenan Andera
* Lee Jamal Amell
* Ty Isaiah Amith
* L Vernon Angela
* Antwan Al Antal
* R Vernon Andera
* L Keenan Angela
* Ed Isaias Aries
* Art Jamal Attal
* Elmo Adan Aumen
* Shane Peter Ast
* Antwan Al Attal
* Otto Alan Auton
* Isreal Al Avril
* Elmo Alan Aumen
* Otto Adan Auton
* Elmo Alan Armen
* Norman Asa Arns
* Isreal Asa Aris
* Elmo Adan Armen
* Alva Adan Arvan
* Alva Alan Arvan
* Otto Adan Arton
* Otto Alan Arton
* Otto Adan Afton
* Otto Alan Afton
* Eddie Jere Ader
* Duane Reyes Ady
* Isaias Adam Aid
* Isaias Adan Aid
* Isaiah Adam Aid
* Isaiah Adan Aid
* Lyle Bob Abella
* Blake Peter Abt
* Ira Jamar Abair
* Ira Lamar Abair
* Chase Reyes Acy
* Lee Jamal Adell
* Tobias Asa Abts
* Derick C Acorda
* Otto Adan Aiton
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Aron Adan Aloan
* Aron Alan Aloan
* Amos Adan Aloan
* Amos Alan Aloan
* Arlie Gene Alan
* Arlie Rene Alan
* Otto Alan Aiton
* Nigel Al Alagna
* Cecil Al Alecca
* Al Isaias Alias
* Arlie Jere Alar
* Bradly L Aldaba
* Arlie Jewell Aw
* Emile Jere Dier
* Elijah Asa Dies
* Emile Gene Dien
* Emile Rene Dien
* Rey Reyes Eayrs
* Roy Reyes Eayrs
* Les Dewey Easly
* Ray Reyes Eayrs
* Earl E Deserres
* Eddie Derek Der
* Earle Deserres
* Stefan Asa Dess
* Steve Pete Dest
* Ezra E Deserres
* Shelby Bob Deso
* Royce Les Eayrs
* Eddie Ben Elden
* Eddie Ken Elden
* Eddie Ken Eiden
* Eddie Len Eiden
* Chi Derek Elick
* Lee Solomon Elm
* Eddie Len Elden
* Ali Keven Elian
* Lee Jewel Edell
* Arlie Leo Edlao
* Royce Wes Eayrs
* Ed Steven Ebsen
* Al Steven Ehsan
* Eddie Ben Eiden
* Reuben Ed Efurd
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* Earle Rene Bren
* Robert Rory Bro
* L Rocco Cachola
* L Royce Cachola
* Royce Rene Byrn
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Otto Adan Axton
* Otto Alan Axton
* Adrian Asa Bras
* Earle Gene Bren
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Leo Gene Debold
* Leo Jere Debold
* Isaias Asa Dais
* Andre Derek Dar
* Leonel E Debold
* Lionel E Debold
* Leo Pete Debold
* Leo Rene Debold
* N Royce Cicconi
* Arlie Gene Clan
* N Boyce Cicconi
* N Rocco Cicconi
* Bruce Jere Cubr
* Isaiah Asa Dais
* Arlie Rene Clan
* Arlie Jere Clar
* Cleo Asa Kazeck
* Dean Rory Roady
* Ryan Rory Roary
* Ed Luigi Riller
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elwood O Rohwer
* Elmo Rory Romey
* Ed Luigi Rigler
* Deon Rory Rhody
* Dion Rory Rhody
* Eli Rene Revier
* Eliseo E Revier
* Ed Luigi Ridler
* Drew Rory Riedy
* Doug Rory Rhudy
* Anibal Asa Rias
* Dino Rory Rondy
* Ivan Asa Salais
* Silas Asa Salsa
* Isaiah a Salais
* Isaias a Salais
* Thomas a Sanots
* Troy Asa Sanots
* Alva Asa Salvas
* Denis Asa Sanda
* Ira Dana Salais
* Cesar Ira Rosca
* Drew Rory Ruedy
* Dong Rory Rondy
* Donn Rory Rondy
* Neil Asa Sabins
* Eloy Asa Sagoes
* Truman Asa Ruts
* Emery Ty Ryneer
* Eli Gene Regier
* Eli Jere Regier
* Ryan Rory Reary
* Ed Steve Reaser
* Eliseo E Regier
* Elmo Rory Remey
* Eli Pete Regier
* Eli Rene Regier
* Ezra Rory Rarey
* Dana Rory Randy
* Dane Rory Randy
* Art Dana Rajtar
* Elmo Asa Rammer
* Donn Rory Randy
* Earl Rory Rarey
* Dino Rory Randy
* Dong Rory Randy
* Eli Gene Renier
* Eddy E Resendes
* Stefan Asa Ress
* Ed Dee Resendes
* Eli Jere Revier
* Eli Pete Revier
* Alva Rory Revay
* Eli Gene Revier
* Eddie Resendes
* Eli Rene Renier
* Eliseo E Renier
* Eli Jere Renier
* Eli Pete Renier
* Art Pete Rentar
* Art Rene Rentar
* Art Gene Rentar
* Art Jere Rentar
* Alva Asa Sarvas
* Emmitt Ty Tomey
* Emmett Ty Tumey
* Emile Pete Tiet
* Emmett Ty Tomey
* Isaiah Asa Vais
* Isaias Asa Vais
* Emmitt Ty Tumey
* Benito Ty Tunby
* Emile Jere Tier
* T Dusty Tatsuta
* T Rusty Tatsuta
* Noe Dana Talent
* Noel Asa Talent
* Emile Gene Tien
* Emile Rene Tien
* Stefan Asa Tess
* Steve Pete Test
* E Otha Vanasten
* Elijah Asa Wies
* Isaiah Asa Zais
* Emile Gene Wien
* Emile Rene Wien
* Emile Rene Zien
* Emile Jere Zier
* Isaias Asa Zais
* Emile Gene Zien
* Stefan Asa Wess
* Emile Rene Vien
* Emile Jere Vier
* Anibal Asa Vias
* Emile Gene Vien
* N Mike Wedekind
* Neil E Wedekind
* Isaiah Asa Wais
* Isaias Asa Wais
* Ali Gene Setias
* Ali Jere Setias
* Noe Rene Serens
* Moses Asa Sesma
* Louis Asa Shula
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Noe Pete Serens
* Ezra Asa Sayres
* Rueben E Sebers
* Reed Asa Savers
* Earl Asa Sayres
* Noe Gene Serens
* Noe Jere Serens
* Miles Asa Selma
* Myles Asa Selma
* Emile Gene Sien
* Thad Asa Tabatt
* Tuan Asa Tabatt
* Ed Teodoro Ster
* Louie Pete Sult
* Duane Pete Tadt
* Graham Asa Tags
* Leo Dana Tabolt
* Leon Asa Tabolt
* Antwan Asa Stas
* Al Luigi Sillas
* Ed Luigi Sirles
* Emile Rene Sien
* Emile Jere Sier
* Louis Asa Soula
* Al Teodoro Star
* Ollie Pete Slot
* Edison O Solies
* Shelby Bob Leso
* Stefan Asa Less
* Tony Lyle Lente
* Zane Lyle Lenze
* Bret Lyle Liebe
* Elijah Asa Lies
* Anibal Asa Lias
* Robt Lyle Libre
* King Lyle Lenke
* Lee Dana Layell
* Eddy Lyle Ledee
* Arlie Keven Lav
* Lee Dana Lavell
* Lyle Lyle Lelle
* Kent Lyle Lenke
* Theo Lyle Leete
* Trey Lyle Leete
* Gene Lyle Longe
* Gino Lyle Lynge
* Isaiah Asa Mais
* Cecil Eli Lucci
* Gene Lyle Lynge
* I Otha Masaitis
* C Mike Mehelich
* Isaias Asa Mais
* Eddy a Marander
* Cecil Ali Lucci
* Daryl Eli Lordi
* Earl Lyle Loree
* Gino Lyle Longe
* Daryl Ali Lordi
* Ollie Peter Lot
* Paul Lyle Loupe
* Ezra Lyle Loree
* Gary Lyle Lorge
* Alvaro R Krivak
* Cletus U Kubeck
* W Rocky Knknown
* Adrian Asa Kras
* Duane Pete Ladt
* Isaiah Asa Lais
* Robt Lyle Labre
* Lee Dana Ladell
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Keenan Asa Keks
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Stefan Asa Kess
* Isaias Asa Lais
* Kurt Lyle Larke
* Vern Lyle Larve
* Kirk Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Lee Dana Lasell
* Shane Pete Last
* Karl Lyle Larke
* Dane Lyle Lande
* Dino Lyle Lande
* Elmo Asa Lammel
* Dana Lyle Lande
* Zane Lyle Lanze
* Dirk Lyle Larde
* Dong Lyle Lande
* Donn Lyle Lande
* Stefan Asa Mess
* Genaro R Orengo
* Isreal Asa Oris
* Otto Everett or
* Adrian Asa Oras
* Al Teodoro Otar
* Santo Coy Ounsy
* Morgan Asa Orms
* Murray Asa Orms
* Teodoro O Omoto
* Steve Pete Oest
* Emile Gene Oien
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Leo Solomon Olm
* Emile Rene Oien
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raemer
* Eddy Asa Raider
* Eddy Asa Radder
* Eddy Asa Raeder
* Isaias Asa Rais
* Antwan a Rajtar
* Elmo Asa Raimer
* Isaiah Asa Rais
* Adrian Adan Rad
* Isaias Asa Pais
* Elijah Asa Pies
* Ollie Jewell Ow
* Isaiah Asa Pais
* Rupert Rory Pro
* Adrian Adam Rad
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Isaias a Narain
* Ivan Asa Narain
* Steve Pete Nest
* Ernie Peter Net
* Ed Steve Neisen
* Ed Steve Nessen
* Isaiah a Narain
* Shannon Z Naasz
* Odis Asa Nacion
* Anibal Asa Mias
* Al Luigi Millam
* Otto Asa Nanton
* Ira Dana Narain
* Olin Asa Nacion
* Otis Asa Nacion
* Ernie Keven Nev
* L Damon Odonald
* L Daron Odonald
* L Aaron Odonald
* L Carol Odonald
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* L Jarod Odonald
* Eddie Jere Oder
* Austin I Nissan
* Elliot O Nowlen
* Emile Jere Nier
* Ian Solomon Nim
* Neal Bob Obiano
* Noah Bob Obiano
* Elroy Ty Nygren
* Emery Ty Nyreen
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5733 "glurk"] (non-homophonic solutions) ==
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Angelo Lyle Gay
* Andre Reyes Day
* Shane Pete Mast
* Shane Pete Fast
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Dean Rory Ready
* Luis Rory Reily
* Gino Lyle Lange
* Louie Pete Ault
* Edison O Rosier
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Arlie Dewey Law
* Rob Dewey Embry
* Eli Dana Rapier
* Elmo Rory Ramey
* Ali Rufus Urias
* Chi Derek Edick
* Otis Asa Nation
* Ali Reyes Elias
* Art Solomon Tam
* Andre Jewel Daw
* Dino Lyle Linde
* Dino Lyle Lunde
* Dino Lyle Lynde
* Arlie Reyes Lay
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Dong Lyle Lunde
* Delmar Asa Olds
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Odis Asa Nation
* Leif Rory Reily
* Elmo Asa Raymer
* Hai Solomon Ihm
* Chi Derek Emick
* Daryl Al Ilardi
* Arlie Rey Emlay
* Chi Derek Enick
* Trevor O Howeth
* Louie Pete Hult
* Chet Asa Kazeck
* Shane Pete Kast
* M Vernon Ingemi
* Neil Asa Garing
* Shane Leo Eraso
* Israel E Gehrig
* Elijah Asa Fies
* Chi Derek Erick
* Trevor O Horeth
* Chi Derek Evick
* L Vernon Angela
* Elmo Adan Aumen
* Shane Peter Ast
* Elmo Alan Aumen
* Elmo Alan Armen
* Elmo Adan Armen
* Duane Reyes Ady
* Blake Peter Abt
* Chase Reyes Acy
* Derick C Acorda
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Elijah Asa Dies
* Shelby Bob Deso
* Royce Les Eayrs
* Chi Derek Elick
* Ali Keven Elian
* Royce Wes Eayrs
* Al Steven Ehsan
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* L Royce Cachola
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Arlie Gene Clan
* Arlie Rene Clan
* Cleo Asa Kazeck
* Dean Rory Roady
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elmo Rory Romey
* Ed Luigi Rigler
* Ed Luigi Ridler
* Doug Rory Rhudy
* Dino Rory Rondy
* Dong Rory Rondy
* Truman Asa Ruts
* Dana Rory Randy
* Dane Rory Randy
* Dino Rory Randy
* Dong Rory Randy
* Benito Ty Tunby
* Noel Asa Talent
* E Otha Vanasten
* Elijah Asa Wies
* N Mike Wedekind
* Ali Gene Setias
* Ali Jere Setias
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Louie Pete Sult
* Leo Dana Tabolt
* Leon Asa Tabolt
* Ed Luigi Sirles
* Al Teodoro Star
* Shelby Bob Leso
* Elijah Asa Lies
* Robt Lyle Libre
* Arlie Keven Lav
* Gino Lyle Lynge
* C Mike Mehelich
* Daryl Eli Lordi
* Gino Lyle Longe
* Daryl Ali Lordi
* Gary Lyle Lorge
* Cletus U Kubeck
* Duane Pete Ladt
* Robt Lyle Labre
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Kurt Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Shane Pete Last
* Dino Lyle Lande
* Dana Lyle Lande
* Dirk Lyle Larde
* Dong Lyle Lande
* Santo Coy Ounsy
* Morgan Asa Orms
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raimer
* Elijah Asa Pies
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Odis Asa Nacion
* Otis Asa Nacion
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* Elroy Ty Nygren
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5676 "PBFred"] ==
* Evil Anal Aziel
== From doranchak [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=30#p22403 (1)] [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=40#p22438 (2)]==
* A McNamara Scar
* Ate severed ear
* Trove Behemoth
* Spiro Motorist
* Laura Catapult
* Alice Venetian
* Agile Venetian
* Lebanon Enable
* Indiana Saudis
* Extras Adopted
* Athlete Lethal
* Achieve Lethal
* a Fine Venetian
* of Flanagan Fog
* to One Behemoth
* Extras Adapted
* Training Neat
* Chinese Eel Ice
* Artists Use Tau
* Our Bananas Ron
* Its Revered Sir
* Our Faraway Row
* Old Bikinis Don
* Of These Men Tom (or Of The Semen Tom)
* Greats To The Go
* Or I Was A Nation
* O He Was A Face Of
* [http://www.zodiackillerciphers.com/?p=152 Over 2,700 phrases from Project Gutenberg experiment]
* [https://docs.google.com/spreadsheets/d/13R16xILq6XIWTklErwZq7ltod7EG08-zeiG0AnAtsl4/edit?usp=sharing Another Project Gutenberg experiment, scanned 61.5 GB of text]
* [http://www.zodiackillerciphers.com/?p=467 From article], person names:
** Chastity Tracy
** Erica Natalie T
** Islami M Amelia
** Eddie Resendes
** Ernie Zerenner
** Aileen Enerlan
** Chitumu Eunice
** Ariyana Mariam
** Sripada Harish
** Ali Raja Mariam
** Arriaga Laura L
** Duitama David D
** Steve Menezes N
** Arriaza Laura L
** Arizala Maria M
** Adriana Laura L
** Aziz a Zahaniah
* [http://www.zodiackillerciphers.com/?p=467 From article], phrases / word combinations:
** Sarah The Horse
** Uncle Peter Cut
** Achieve Lethal
** Obscene Nelson
** Extreme Reuter
** Emperors Ropes
** Leigh The Haile
** Kane Pops Punks
** Gareth Tot Ergo
** Niece Gene Penn
** Drop Rarer Code
** Door Non-Encode
** Iraq Alan Again
** All Banana Alan
** Alice Venetian
** Laura Catapult
** Afghan Amalgam
** Reassess Scars
** Clara Cataract
** Shannon Encase
** Okinawa Nation
** Indiana Saudis
** Regan Adalard
** Drippy Peptide
** Outlet Erector
** Akira Canadian
** Adriana Marram
** Mary Nina Norma
** Robert Rory Bro
** Smile Pete List
** Mary Tate Terme
** Mary Gags Germs
** Ryan Amaya Gary
** Daniel Eye Andy
** Eats Bobs Bates
** Kill Baby Bulky
** Shit Pipe Poise
** Eric Alan Alien
** Slave Pete Last
** Extra War After
** Murder Eye Army
** Clara Fatal Act
** Encoded Odd CEO
** [http://zodiackillerciphers.com/z13wordsearch-results-2-sorted.txt List of 283 phrases / word combinations that use two words]
** [http://zodiackillerciphers.com/z13wordsearch-results-3-sorted.txt List of 1,283,443 phrases / word combinations that use three words]
* From another corpus test for [https://www.reddit.com/r/ZodiacKiller/comments/axqx4z/z13_my_name_is_cipher/ reddit post]:
** Chief of Africa
** Uncle Peter Cut
** of Hair It Is Hot
** of These Newton
** at Me O Son of Man
** a Wide Venetian
** a Ripe Venetian
** Avis, a Canadian
** India. Was, and Is.
** I Saw Alan Again
** I Was a Man Again
** I Had a Man Again
** Near a Way As Any
** Claus Asks Jack
** Guest at Otsego
** One Has a Name on
** One Had an Axe on
** As if a Canadian
** Oh No It It Is Not
** Is That As Art Is
** Nearer Eden and
** Niagara Day And
** [http://zodiackillerciphers.com/z13-corpus-solutions.txt Full unprocessed results]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4305&p=69616 More results from corpus scanning:]
** So I'm a Satanist
** So I'm a Fatalist (from glurk)
** A Dog, a Cat, a Goat
** or Steve Nelson
** As I Had an Asian
** a Kid: a Canadian
** Emperor's Ropes
** As Real As Auras
** That I Die, I Hate
** One Has a Name on
** I've Had an Axe in
** Spectate These
** if I Was a Nazi in
** I Eat a Banana in
** As I'm a Canadian
** I Was a Canadian
** Leave Helen All
** Edit As an Alien
** Shakalaka Mask
** Shit! a Natalist!
** Shit! a Fatalist!
** Shit! a Satanist!
** Is a Pagan Again
** Extra Caracter
** and Gamal Abdal
** Donut. It Stands.
** Al Is a Canadian
** Reign on Entire
** I've Had a Dane I.D.
** Least It Steals
** Ratio, Do You Try?
** Said As a Taoist

== From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6406 "Deryk"] ==
* Male, Initial: M.T.
== From [https://www.tapatalk.com/groups/zodiackillerfr/my-name-is-zodiac-t2276-s20.html#p139086 "MickCal"] ==
* OL STEVE NELSON
== From [https://discord.com/channels/996952324150931477/996952376894292018/1135335122527342604 "Toad"] ==
* AMIGO COLONIAL
== From [https://discord.com/channels/996952324150931477/996952376894292018/1033254655381217320 "Antisquid42"] ==
* John E. Heresh Jr.
* Donald LeLinde
* Neal O’Donovann
* Doug Lyle Laude
* Chip O. Kozowicz
* Seth Everett Sr.
* Andrew E. Levdal
* Paul Lyle Loupe
* Shiloh Oto List
* Juan O. Corona Jr.
* Frank X. LeLoafe
* Leo Solomon Olm
== From [http://zodiackillerciphers.com/z13_2_word_solutions.txt "rando"] ==
* [http://zodiackillerciphers.com/z13_2_word_solutions.txt 3,142 2-word solutions]

== Partial solution from [http://zodiackiller.21.forumer.com/viewtopic.php?p=119889#119889 "granny101"] ==
* ILLNEVETELLIT ("I'LL NEVER TELL IT", with the "R" missing)
== From [https://www.tapatalk.com/groups/zodiackillerfr/solution-to-the-challenge-t11196.html#p264079 "CipherS0luti0ns"] ==
* SOLVE REVEALS V

= Solutions that fit if you first reverse the cipher =

TODO

= Solutions that fit the ciphertext if you permit anagramming =

Rearranging the cipher text significantly reduces the constraints on possible solutions. As [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=20#p13716 "glurk"] points out, anagramming the 13 symbols permits a very large variety of possible solutions, which makes it nearly impossible to validate any given solution derived this way.

Here are some examples of solutions that arise from anagramming:

* [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=40#p13807 Small sampling from "sincos"]
* From doranchak:
** 13-letter English words that have the same letter distribution as the symbols of the cipher:
*** international, participation, concentration, interventions, investigating, participating, inappropriate, investigative, authoritarian, mediterranean, intentionally, accommodation, strengthening, commissioners, differentiate, collaborators, incorporation, unwillingness, mismanagement, superstitious, mathematician, nationalities, instantaneous, nationalistic, inconsistency, choreographer, preponderance, condescending, applicability, contingencies, indeterminate, sarcastically, temperamental, disillusioned, prerequisites, intelligences, irreplaceable, headquartered, reincarnation, proportionate, appropriating, inclusiveness, preservatives, ornamentation, uninteresting, incapacitated, contaminating, irrationality, abolitionists, improprieties, structuralist, sharecroppers, solicitations, intermarriage, arbitrariness, impermissible, disconnection, professorship, scintillating, insufficiency, spectroscopic, satisfactions
** Small sampling of 13-letter surnames that have the same letter distribution as the symbols of the cipher:
*** radhakrishnan, bhattacharjee, villavicencio, chattopadhyay, oluwatobiloba, degraffenreid, knappenberger, brandenburger, hebblethwaite, rathakrishnan, degraffenried, sahasrabuddhe, stamatopoulos, schlegelmilch, sastrowardoyo, konstantinova, muruganantham, thorsteinsson, madhusoodanan, wojciechowicz, hintermeister, klingenberger, vansteenkiste, raveendranath, blankenbiller, messerschmitt, abdollahzadeh, vlaisavljevic, stamatopoulou, giacomantonio, gebregziabher, gardarsdottir, blattenberger, agustiningsih, sverrisdottir, shirmohammadi, reichenbacher, schottenstein, christophoros, javakhishvili, sundareswaran, schiermeister, kaluhiokalani, natsvlishvili, monteferrante, ntakirutimana, derakhshandeh, winternheimer, spangenberger, liechtenstein, heiderscheidt, chandrarathne, shettlesworth
** [http://zodiackillerciphers.com/all-names-z13-list2-sorted.txt A sampling of 69,607 common first-last name combinations] that have the same letter distribution as the symbols of the cipher.
*** [http://zodiackillersite.com/viewtopic.php?p=18552#p18552 (Original broken forum link)]
* From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6376 Tom Voigt]:
** knickerbocker
** [http://zodiackiller.21.forumer.com/viewtopic.php?p=120299#120299 aintgonnatell]
* From [http://www.santarosahitchhikermurders.com/ Deb Silva]:
** [http://en.wikipedia.org/wiki/Bobby_Beausoleil Bob Beausoleil]
* From Anonymous:
** Jimmy Phillips (also credited to [http://zodiackiller.fr.yuku.com/topic/3827/Jimmy-Phillips alanbenjy])
* From Christer Böke:
** Frank Frazetta ([http://zodiackillersite.com/viewtopic.php?f=63&t=1275 Tim Holt] was drawn by Frank Bollle and Frank Frazetta)
** Grant Santiago
* From [https://www.tapatalk.com/groups/zodiackillerfr/simple-solve-for-the-my-name-is-t8738.html#p145360 jaydeezodiachunter]:
** Debbie Faraday

= Solutions that fit if you relax other constraints of the cipher =

Solutions that fit if you allow all three "circled 8" symbols to be wildcards:
* From Michael Kelleher:
** thebigsecrete
Solutions that are produced via multiple operations:
* From [http://www.zodiackillerciphers.com/?p=46 Lyndon Lafferty]:
** NAME GRANT, or NAME IS GRANT
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/detailed-solution-to-z13-and-z32/ Faycal Ziraoui's solution]
A solution that applies the 408 key and interprets some symbols as nulls:
* from [http://zodiackiller.fr.yuku.com/topic/6839/Zodiacs-Name-using-408-Key Rembrandt]:
** ED SHAW
Solutions with one name part in the middle, and another name part split in half and written backwards:
* [http://www.zodiackillersite.com/viewtopic.php?p=69126#p69126 DEBBIE FARADAY]

= Other interpretations =

* "My name is" contains 8 letters. The cipher text contains 8 letters and 5 special symbols. The special symbols contain Zodiac's name and the rest just mean "My name is" (Source: Jeppesen)
* [https://www.tapatalk.com/groups/zodiackillerfr/general-book-discussion-for-hunted-the-zodiac-murd-t10141.html#p197345 "Set addition" interpretation of Z13 by Doug Oswell], resulting in solution: "FROM TED KACZYNS[K]I"
* [https://www.tapatalk.com/groups/zodiackillerfr/paul-astrup-s-theory-meteorological-symbols-challe-t10261.html#p202558 Weather symbols]
* The line after "My name is" is roughly above symbols that resemble "Tom" spelled backwards. (Source: David Cauley via YouTube comments)

Halloween card

2024-01-19T00:48:27Z

Admin: /* Cipher-related */

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Cattle brands ===

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."
* [https://forum.zodiackillerciphers.com/community/postid/79587/ A reference to Z340's transposition scheme]

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]
* [https://www.tapatalk.com/groups/zodiackillerfr/wide-flange-beam-gaik-t2170.html "GAIK" in Brahmi alphabet]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Possible graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Halloween card

2024-01-08T15:18:49Z

Admin: /* Writing systems / early alphabets */

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Cattle brands ===

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]
* [https://www.tapatalk.com/groups/zodiackillerfr/wide-flange-beam-gaik-t2170.html "GAIK" in Brahmi alphabet]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Possible graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Halloween card

2024-01-08T15:14:22Z

Admin: /* Maps / Geography */

__TOC__

= The mysterious symbol =

== Description ==

This symbol appeared [https://zodiackiller.com/HalloweenCard.html in the card] Zodiac sent to Paul Avery on Oct 27, 1970. It also appeared on [https://zodiackiller.com/HalloweenCardEnvelope.html the envelope] the card came in.

[[File:Card_symbol_1.png]]

[[File:Card_symbol_2.png]]

It is sometimes called the "VF" symbol.

== Interpretations and comparisons ==

=== Construction ===

* Wide flange beam. From Robert Graysmith's book "Zodiac":

''As for the new Zodiac symbol, readers as far away as Detroit wrote to say it represented a Wide Flange Beam, a structural steel shape used in building construction. Some felt that Zodiac was some sort of civil engineer.''

=== Chemistry ===

* [http://zodiackillersite.com/viewtopic.php?p=365#p365 Chemical compound 1-Pentene] (scroll down a bit to see the section about pentenes)
** Image:

[[File:1-pentene.jpg]]

=== Cattle brands ===

* Red Ryder ranch cattle brand symbol ("flying V F bar")
** [https://zodiackillersite.com/viewtopic.php?f=63&t=1266 Details]
** Image (the brand appears on the cow in the upper right corner):

[[File:Red_ryder_ranch.jpg]]
* Example of that brand on a live cow:

[[File:running_brand_dsc_0069.jpg]]

* [https://www.reddit.com/r/ZodiacKiller/comments/mgu26e/halloween_card_symbol_a_kentucky_ranch_brand/ Kentucky Ranch brand]
** [https://www.kyagr.com/statevet/documents/AM_BrandBook013118.pdf See bottom of page 32 in this PDF]

Excerpt:

[[File:Veluzat_farm.jpg]]

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-real-name-william-mcduff-andrew-t9690-s15640.html#p206897 Livestock brands in South Dakota]

=== Maps / Geography ===

* [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 Intersection in Vallejo]
* [http://www.zodiackillersite.com/viewtopic.php?p=83751#p83751 Map overlay]
* A silhouette of [https://en.wikipedia.org/wiki/Mount_Diablo Mount Diablo]
** "An abstraction of the Zodiac's eyes and car headlights emerging from the Diablo mountain range." [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h18mtap/ (source)]
* [https://nicolam6.wixsite.com/faceofthezodiac/post/zodiac-neteorology "Diamond sign" from Japanese treasure map]

Excerpt:

[[File:Japanesediamondsign2.jpg]]
* [https://www.facebook.com/photo?fbid=10159233155543490&set=p.10159233155543490 Another map overlay example]
** [http://zodiackillerciphers.com/images/211164342_10159233155553490_3106341937988433783_n.jpg (Image)]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-as-a-map-t10924.html Another map overlay example]
* Weather map annotations, such as [https://en.wikipedia.org/wiki/Station_model station models] and [https://www.weather.gov/hfo/windbarbinfo wind barbs]

=== Cipher-related ===

* [https://www.evernote.com/l/AAHtXB4zRJBON5-S7V85ujVjMl3RSwSMgvk A method of finding the symbol in Z340]
* [https://www.travelingtemplar.com/2019/01/mark-masonry.html Mason marks]
** [http://zodiackillerciphers.com/images/Polish_20210622_065859339_compress69.jpg Example from "N!CK"]
* [https://www.evernote.com/l/AAHFAMg7ZlFJbpBvNFlXWD_aIWy-m3IK74E Another idea about finding the symbol in Z340]
* [https://en.wikipedia.org/wiki/Pigpen_cipher A stylized form of pigpen cipher]
* Combined symbols from Z408 (/, V, and F).
** They would decode to K, B, and S, respectively (source: comment by Seedy on Let's Crack Zodiac - Episode 12 )
*** "How odd would it be that those initials K.B.S. show up in the 408 cipher as the fourth letter of the first line. The second letter of the second line. With S being the eighth letter of the third line. Maybe K.B.S. Is a birthdate? 4-2-8. The second half of the 408 cipher at the 4-2-8 spelled M.I.T. The third section spelled out A.C.E. There is a doctor of chemistry that went to work at M.I.T. sometime after the 408 was written. His initials are K.B.S. Maybe his nickname was Ace? His first and last name fit the Z13. He was living in Palo Alto at the time some of the letters were mailed in."

=== Writing systems / early alphabets ===

* [https://en.wikipedia.org/wiki/Bat_Creek_inscription Bat Creek inscription]
** Apparently a Newsweek article about the Bat Creek Stone was published just one week before the Zodiac mailed the Halloween card [https://www.reddit.com/r/ZodiacKiller/comments/9ik6jy/3_questions_about_the_halloween_card_symbols/e6kesu3/ (source)]
** Excerpted symbol from the [https://en.wikipedia.org/wiki/Bat_Creek_inscription#/media/File:Bat_Creek_Exam_5-28-10.JPG full image]:

[[File:Bat-creek-symbol.png]]

* [https://www.youtube.com/watch?v=cQj6KPlK7Nk Ogham alphabet]
* Mike Rodelli [https://zodiackillersite.com/viewtopic.php?p=15517#p15517 proposes] the symbol is a combination of the Norse runes Ansuz and Laguz.
** Ansuz: ᚨ
** Laguz: ᛚ
** [https://en.wikipedia.org/wiki/Elder_Futhark Elder Futhark]
* [http://www.norwayheritage.com/Property-Marks-in-Rural-Norway.htm Early Norwegian house marks (bumerker)]
* [https://www.wikiwand.com/en/Telegraph_code Cooke and Wheatstone codes]
* French hobo system, [https://www.symbols.com/symbol/friendly-people "Here live friendly people"]
** [http://zodiackillerciphers.com/images/symbols/2370_friendly-people.png Image]
* yōd symbol in [https://en.wikipedia.org/wiki/Paleo-Hebrew_alphabet Paleo-Hebrew alphabet]
* yod symbol in [https://en.wikipedia.org/wiki/Phoenician_alphabet Phoenician alphabet]

=== Other symbology ===

* [https://www.reddit.com/r/ZodiacKiller/comments/nwc39f/symbol_on_halloween_card_envelope_sent_to_paul/h1dcqlg/ Peace sign interpretation from a draftperson's perspective]
** [https://imgur.com/hacze5I Image]

=== Names/Monograms ===

* [https://www.tapatalk.com/groups/zodiackillerfr/macgruber-t9690-s4150.html#p171648 Nickname/initials of suspect]
** [http://zodiackillerciphers.com/images/10763040_3ca491f0cbe0a2a890f64274795af943_t.png Image]
* [https://www.tapatalk.com/groups/zodiackillerfr/symbol-similar-to-the-symbol-from-halloween-card-t10048.html#p189332 Stylized abbreviation for "Nevada" on envelope of letter allegedly sent by DB Cooper]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Similar logos ===

* [https://www.vfinancialservices.com/ V-Financial Services]
** [http://zodiackillerciphers.com/images/v-financial-horizontal-logo.png Image of logo]

=== Possible graffiti ===

* Zone of Silence sign
** [https://www.tapatalk.com/groups/zodiackillerfr/zone-of-silence-t10331.html Discussion]
** [https://science.howstuffworks.com/science-vs-myth/unexplained-phenomena/zone-silence.htm Article with image of sign]
*** [http://zodiackillerciphers.com/images/zone-of-silence.png Image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-3.jpg Image (higher quality)]
** [https://www.facebook.com/Qic.Facts/photos/didyouknowmexico-has-a-place-called-the-zone-of-silence-where-clocks-dont-work-r/2751520224874802/ Facebook post with larger image]
*** [http://zodiackillerciphers.com/images/zone-of-silence-2.jpg Image]

= Other aspects of the Halloween Card =

* Applying +9 Caesar shift to "BY GUN" yields "KHPDW". Decoding "KHPDW" with Z408 key yields "STINE", as in Paul Stine. (Source: Jade Goldstone)

Solution to the 340

2024-01-05T20:13:58Z

Admin: /* Friday, December 11th 2020 */

== Raw text of the solution, after reversing transposition ==

''Presumed errors are in boldface:''

: I HOPE YOU ARE HAVING LOTS OF F'''A'''N IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRING'''O''' UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECA'''A'''SE IT WILL SEND ME TO PARAD'''L'''CE
: ALL THE SOO'''H'''ER BECAUSE '''E''' NOW HAVE ENOUGH SLAVES
: TO WOR'''V''' FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I '''V'''NOW THAT MY NEW
: LIFE IS LIFE WILL BE AN EASY ONE IN PARADICE DEATH

''With errors corrected:''

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE IS LIFE WILL BE AN EASY ONE IN PARADICE DEATH

== Interpretations of the seemingly misplaced words "LIFE IS" and "DEATH" ==

=== Group "LIFE IS" with "DEATH" ===

Example 1:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE WILL BE AN EASY ONE IN PARADICE.
: '''LIFE IS DEATH'''

Example 2:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE WILL BE AN EASY ONE IN PARADICE.
: '''DEATH IS LIFE'''

Example 3:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: '''LIFE IS DEATH'''. LIFE WILL BE AN EASY ONE
: IN PARADICE

Example 4:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH. '''LIFE IS DEATH'''. I AM NOT AFRAID
: BECAUSE I KNOW THAT MY NEW LIFE WILL BE AN EASY
: ONE IN PARADICE

Example 5:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE WILL BE AN EASY ONE: '''DEATH IS LIFE'''
: IN PARADICE.

''Additional speculation: The original ciphertext starts with the letters "HER", so perhaps the intended message formed from these fragments is "HER LIFE IS DEATH".''

=== Change "THAT" to "WHAT" ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW '''WHAT''' MY NEW
: LIFE IS: LIFE WILL BE AN EASY ONE IN PARADICE DEATH

=== "MY DEATH IS NEW LIFE" ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY
: '''DEATH IS NEW LIFE'''. LIFE WILL BE AN EASY ONE
: IN PARADICE

=== "WHERE DEATH IS LIFE" (suggested by Brandon Baskin) ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASNT ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME EVERYONE ELSE HAS NOTHING WHEN THEY
: REACH PARADICE SO THEY ARE AFRAID OF DEATH I AM
: NOT AFRAID BECAUSE I KNOW THAT MY NEW LIFE WILL
: BE AN EASY ONE IN PARADICE '''WHERE DEATH IS LIFE'''

== Verifications of the solution ==

* FBI confirmations:
** [https://twitter.com/FBISanFrancisco/status/1337477701825925120 FBI statement on their twitter account]
** [https://www.cnet.com/science/zodiac-killer-message-known-as-340-cipher-solved-after-51-years/ Article with excerpt from more detailed FBI statement]
** The full press release that was sent to me from the FBI press office:
*** ''The FBI has a team of cryptanalysis experts that decipher coded messages, symbols, and records from criminals known as the Cryptanalysis and Racketeering Records Unit. CRRU regularly works with the cryptologic research community to solve ciphers. On December 5, 2020, the FBI received the solution to a cipher popularly known as Z340 from a cryptologic researcher and independently verified the decryption. Cipher Z340 is one of four ciphers attributed to the Zodiac Killer. This cipher was first submitted to the FBI Laboratory on November 13, 1969, but not successfully decrypted. Over the past 51 years CRRU has reviewed numerous proposed solutions from the public–none of which had merit. The cipher was recently solved by a team of three private citizens. The Zodiac Killer case remains an ongoing investigation for the FBI San Francisco division and our local law enforcement partners. The Zodiac Killer terrorized multiple communities across Northern California and even though decades have gone by, we continue to seek justice for the victims of these brutal crimes. Due to the ongoing nature of the investigation, and out of respect for the victims and their families, we will not be providing further comment at this time.''
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/why-the-transposition-in-the-340-solution-is-inevitably-correct/#post-86366 f.reichmann's argument based on unicity distance]
*** [https://zodiackillerfacts.com/news-and-updates/breaking-news-the-zodiacs-340-cipher-has-been-solved/ Full FBI press release was included in Michael Butterfield's article]
* [https://www.youtube.com/watch?v=hIrOftXgibg Nils Kopal's verification]
* [https://eprint.iacr.org/2021/1620 ''Unicity distance of the Zodiac-340 cipher'' by Joachim von zur Gathen]

== More info ==

* [https://www.youtube.com/watch?v=-1oQLPRE21o Solution video 1]
* [https://www.youtube.com/watch?v=UfrFSrI05hk Solution video 2]
* [http://zodiackillerciphers.com/images/z340-key.png Image of the Z340 substitution key]
* [[Compilation of news reports about the solution]]
* [http://www.zodiackillerciphers.com/?p=869 Sam's slides] from his presentation, [https://www.youtube.com/watch?v=iuNyQ44JYxM "The Quest to Solve the Zodiac 340 Cipher"].
* [[Transposition matrices]]

== Timeline of arriving at the solution ==
''Times reported are in Eastern time in the USA''
=== Saturday, January 3, 2015 ===
* 05:56PM: [http://www.zodiackillersite.com/viewtopic.php?p=27087#p27087 Jarl's first post about availability of his new codebreaking software, AZdecrypt. (broken link)]
** [https://forum.zodiackillerciphers.com/community/zodiac-cipher-mailings-discussion/azdecrypt-beta-0-94/ Working link]

=== Tuesday, July 28, 2015 ===
* 01:02PM: Jarl posts his observations including period 19 bigram repeats [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (original version in Wayback)] [https://zodiackiller.net/community/postid/39170/ (Live version)]
=== Wednesday, August 5, 2015 ===
* 12:45AM: Daikon posts his observations including period 19 bigram repeats [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (original version in Wayback)] [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ Live version]
=== Wednesday, January 16, 2019 ===
* 09:12AM: Sam Blake's first contact with me, via comment on [https://www.youtube.com/watch?v=3Hk__Hk5c9M my 2018 ACA presentation video on Youtube.]
=== Thursday, August 1, 2019 ===
* 09:14PM: Sam Blake starts emailing me enumerations of Z340

=== Sunday, May 17th, 2020 ===
* 07:03AM: Jarl posts a [https://forum.zodiackillerciphers.com/community/zodiac-cipher-mailings-discussion/z340-multiple-transcription-rectangles/ transposition of the 340] which is extremely close to the correct final result.
** [http://zodiackillerciphers.com/jarl-transposition-3-sections-period-19.txt Transcription]
** [http://zodiackillerciphers.com/jarl-transposition-3-sections-period-19-pt.txt Plaintext resulting from applying final Z340 key to his transposed ciphertext]
** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/z340-multiple-transcription-rectangles/ Old broken link]

=== Wednesday, December 2nd, 2020 ===
* 04:14PM: Began running 655,088 ciphers, the cumulative collection of all cipher enumerations and decimations Sam Blake has sent me to date, through AZDecrypt v1.19 with default settings (except for loading jarlve's reddit 6-grams). Had run many of them before, but this time I wanted to be more careful about sorting the results based on the cipher lengths (some manipulations remove parts of the cipher, which sometimes leads to azdecrypt reporting higher scores compared to ones for ciphers of length 340).
=== Thursday, December 3rd, 2020 ===
* 12:04PM: Reported an interesting result to Sam from one of his older vertical 3-split decimations
** [http://www.zodiackillerciphers.com/z340_vertical_3split_decimations_9_9_1_19_2.txt Transcription: z340_vertical_3split_decimations_9_9_1_19_2.txt]
*** [http://www.zodiackillerciphers.com/z340_vertical_3split_decimations_9_9_1_19_2_pt.txt Plaintext resulting from applying the final Z340 key to his transposed ciphertext]
** AZdecrypt generated this candidate plaintext:
*** EHOPE YOU ARE HE SING IST TORRA ENN
*** TRYING TO CATCH METH AFTAINT MT ON THE
*** TS SHOT WHICH BRINGS UP ALS IN TABS IT
*** ME NAME OF AR HEED OR THE GAS CHAMBER
*** BECA ATE IT WILD VENT ME ROLER A DICE
*** AI I THE VS SHEN BECAUSE TOO WHA SEEN
*** TIGHT DESERTS WORS ROS ME THERE
*** EVERYONEED HE HAS NOTHING THEN THEY HE
*** ACH PARADICT IS THEY ALREARE AND NORDER
*** THER AMEO EARRE AND BECAUITE IS YOT TV
*** HAT MR NEWE ITLE NEVER IND BAEYN NEIA
*** AT A HOE CDR PET
** A few interesting legible phrases stood out right away:
*** HOPE YOU ARE
*** TRYING TO CATCH ME
*** SHOT WHICH BRINGS UP
*** OR THE GAS CHAMBER
*** HE HAS NOTHING THEN THEY
** Phrases were more noticeable due to the auto-whitespace feature Jarl added for v1.19.
* 03:25PM: Determined the transposition (decimation) steps that were performed for that cipher among Sam's batch.
* 07:50PM: Sam provides details on the 9,9,1,19,2 enumeration, which is actually split into 4 vertical groups of size 9, 9, 1, and 1. A decimation of 19,2 is applied to each group.
* 09:36PM: I reported to Sam my solution to the first 9 lines, obtained by isolating those 9 lines, feeding them into AZdecrypt, but locking in cribs for some of the interesting phrases discovered earlier.
** The plaintext read: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO CATCH ME THAT WASNT ME ON THE TV SHOW WHICH BRING OR PA POINT ABOUT ME I UM NOT A FRA IF OF THE GAS CHAMBER BECUASE IT WILL SEND ME TO PAY UNLCE ALL THE
** The first section contains every symbol used in the entire cipher, so applying the key to the entire cipher text gave this plaintext: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO CATCH ME THAT WASNT ME ON THE TV SHOW WHICH BRING OR PA POINT ABOUT ME I UM NOT AFRAID OF THE GAS CHAMBER BECUASE IT WILL SEND ME TO PAY UNLCE ALL THE SOO HEN BE CURSEE OOW HAVE ENSUGH SLAVER TO WOR V FOV ME WHERE ESERYONE EL HEH US NOTHING WHEN THEY REACH PAY UNICE SO TREY ALREU FAA I FI OF NET TH IF AM NO EA FREA IF BNC ARISE IV YO WT SHAT MR NEW EIW LENESE FLIL BAAYNNE I UADAHO I CFR PET
** Appearance of phrase "THAT WASNT ME ON THE TV SHOW" locked this in as a solid lead towards a real solution. Second 9 lines yielded from the same key have a relatively high score (compared to random plaintext or gibberish) but is somewhat garbled. Also noticed the word DEATH appearing at the very end of the last line of the entire cipher, using same key as the one discovered for the first 9 lines. Asked Sam for help to figure out the remaining 11 lines.
* 10:04PM: Notified Jarl to also ask for his help.

=== Friday, December 4rd, 2020 ===
* 08:04AM: Ran several other decimations from Sam to try to isolate other schemes that might lead to a solve for the remaining 11 lines.
* 09:29AM: Completed a search of over 400,000 AZdecrypt results and determined that the phrase GAS CHAMBER appears in no other result.
* 10:10AM: Ran some more decimations from Sam. Didn't notice anything substantial in the results.
* 11:19AM: First response from Jarl, "It looks genuine!"
* 02:17PM: I report reversed words in the last 2 lines to Sam and Jarl
* 02:23PM: Jarl independently reports reversed words in the last 2 lines.
* 02:31PM: I interpreted the garbled 2nd section to read like this:
** BECAUSE ? SLAVES TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF LETTING ?? BECAUSE I (VOW?)...
* 02:40PM: Refined 2nd section:
** BECAUSE ??? HAVE ENOUGH SLAVES TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF LETTING ?? BECAUSE I (VOW?)...
* 02:58PM: Jarl reports his refined solution:
**I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING
**TO CATCH ME THAT WASNT ME ON THE TV SHOW
**WHICH BRINGS UP A POINT ABOUT ME I AM NOT
**AFRAID OF THE GAS CHAMBER BECAUSE IT WILL
**SEND ME TO PARADICE ALL THE
**
**SOO HEN BECAUSE EOOW HAVE ENOUGH SLAVES TO
**WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
**WHEN THEY REACH PARADICE SO THEY ALRE UFA AID
**I OF DET TH IF AM NO EA FREA ID BN CA AISE IV
**YO WT SHAT MR NEW
**
**EFIL WILL EB NA EASY E
**NONI ECIDARAP DEATH
* 03:18PM: I report my finding about the errors on line 15 (the 6th line of the 2nd section). Several errors are happening on the same line, suggestive of a systematic mistake.
* 03:23PM: Jarl reports his interpretation of the plaintext:
** SO THEY'RE ALL AFRAID OF DEATH I AM NOT AFRAID BECAUSE IT ...
* 04:19PM: I'm considering sending our partial solve to the FBI so they can help us work out the rest of it
* 05:47PM: Decided against reporting the solve early, to give our team more time to work it out. Developed a visualization of the errors on line 15 (6th line of the 2nd section).

=== Saturday, December 5th, 2020 ===
* 01:26AM: Jarl reports progress on the plaintext, resulting from a possible "skip" in the 2nd part. Jarl's latest plaintext:
** I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING
** TO CATCH ME THAT WASNT ME ON THE TV SHOW
** WHICH BRINGS UP A POINT ABOUT ME I AM NOT
** AFRAID OF THE GAS CHAMBER BECAUSE IT WILL
** SEND ME TO PARADICE (ALL THE)
**
** (SOO HEN) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO (THEYRE ALL) AFRAID
** OF DEATH I AM NOT AFRAID BECAUSE IT
** (YO WT SHAT MR NEW)
**
** EFIL WILL EB NA EASY ENO
** NI ECIDARAP DEATH
* 02:16AM: Jarl reports more detail on the skip in the 15th row, and the skip seems isolated to that row. But still some garble happening after that is fixed.
* 02:41AM: Jarl reports discovery that skipping cleartext "LIFEIS" in upper right section of the 2nd block fixes the remaining garbles. Plaintext now only has a few errors remaining.
* 02:50AM: Jarl reports full plaintext:
** I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING
** TO CATCH ME THAT WASNT ME ON THE TV SHOW
** WHICH BRINGS UP A POINT ABOUT ME I AM NOT
** AFRAID OF THE GAS CHAMBER BECAUSE IT WILL
** SEND ME TO PARADICE (ALL THE)
**
** (SOO HER) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO THEY ARE AFRAID
** OF DEATH I AM NOT AFRAID BECAUSE I KNOW THAT
** MY NEW LIFE IS
**
** EFIL WILL EB NA EASY ENO
** NI ECIDARAP DEATH
* 03:44AM: Jarl reports details on steps that were required to fix the 2nd section:
** Right-offset the RATENYRNOSRVSH fragment by 1 becoming HRATENYRNOSRVS. I think he skipped the H by mistake (during homophonic step) and then realized his error going into the 7th row and added the H back in at the end of the 6th row.
** Skip the positions of the "LIFEIS" fragment during untransposition.
** Now after transposition it will result in:
**
** (SOO HER) BECUASE E NOW HAVE ENOUGH SLAVES TO
** WORV FOR ME WHERE EVERYONE ELSE HUS NOTHING
** WHEN THEY REACH PARUDICE SO THEY ARE UFRAID OF
** DEATH I AM NOT AFRAID BECAASE I VNOW THAT MY NEW
**
** Fixing a few errors:
**
** (SOO HER) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
** DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
**
** Since the "LIFEIS" fragment was skipped it can be added in somewhere else, and I think it has to be at the end:
**
** (SOO HER) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
** DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW (LIFE IS)
* 07:56AM: I completed a PDF report of our solution and submitted it to my contacts at the FBI crypto lab.
* 08:02AM: First response from FBI crypto lab, unofficial confirmation
* 08:48AM: Second response, unofficial confirmation
* 08:49AM: Third response, further confirmation, phone call
Not sure about further timing on this day, but during the day the FBI took action on the solution, notifying others in the agency as well as working on a report of the solution to submit back to SFPD, the original requestor. Submission also planned to SF FBI.
=== Sunday, December 6th, 2020 ===
CRRU submitted the solution to FBI San Francisco in the evening.
Waiting for contact with FBI National Press Office to coordinate release of this news.

=== Monday, December 7th, 2020 ===
Talked to FBI National Press Office in the afternoon to discuss release plan. Allowing for all victim notifications to take place prior to releasing the news.
=== Thursday, December 10th 2020 ===
Talked to FBI National Press Office in the afternoon and was informed that final notifications will be completed by the end of the day and that the best time for the news release will be Friday.

[https://www.tapatalk.com/groups/zodiackillerfr/viewtopic.php?p=159817#p159817 Teased the pending release of the news.]

=== Friday, December 11th 2020 ===
* 06:00AM: [https://youtu.be/-1oQLPRE21o Explainer video (Let's Crack Zodiac Episode 5)] switched to Public. I posted the news on many social media outlets and forums, and emailed the LCZ mailing list.
** Post on [https://www.tapatalk.com/groups/zodiackillerfr/the-340-cipher-has-been-solved-t9434.html#p159875 Tom Voigt's forum]
** Post on [https://forum.zodiackillerciphers.com/community/news-wire/z340-has-been-solved/ Mike Morford's forum]
* 01:03PM: First news report by SF Chronicle, [https://twitter.com/KevinChron/status/1337458070570508289 announced by long time Zodiac reporter Kevin Fagan]
* 02:21PM: FBI San Francisco makes a public announcement of the solution [https://twitter.com/FBISanFrancisco/status/1337477701825925120 on their twitter account.]

Over the next several days, many news outlets reported on the solution.
[http://zodiackillerciphers.com/wiki/index.php?title=Compilation_of_news_reports_about_the_solution Click here for a compilation.]

Z13 Solutions

2024-01-03T16:58:11Z

Admin: /* From "rando" */

= Solutions that fit the ciphertext as is =

This section only shows proposed solutions that fit the cipher text "as is". No anagramming or other re-arrangements are used here, and the cipher is considered to be strictly a substitution cipher. Solutions that permit anagramming are very easy to come by, as there are several billion possible string combinations to choose from. Solutions that do not require anagramming are still numerous, however, which increases the difficulty of knowing which one is correct.

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=50&t=1390&p=24191#p24190 "Quill"] ==
* Eddie Penerden
* Stan T E Case (using "8"s as spaces)
* Greg N A Vega (using "8"s as spaces)

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5677 "glurk"] (homophonic solutions) ==
* Steve Pete West
* Adrian a Harrah
* Shannon E Nease
* Steve Pete Best
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Eddie Gene Oden
* Steve Pete Vest
* Barney E Yearby
* Gene Lyle Lange
* Eddie Gene Eden
* Ed Steven Eisen
* E Alva Vanallen
* Angelo Lyle Gay
* Eddie Rene Oden
* Isreal a Sarris
* Carl Bob Abarca
* Elliot O Roller
* Andre Reyes Day
* Ed Steve Nelsen
* Shane Pete East
* Lee Gene Levell
* Eddie Rene Eden
* Rueben E Segers
* Rueben E Severs
* Eddie Gene Aden
* Eddie Dewey Dew
* Shane Pete Mast
* Ed Steve Reeser
* Ed Steve Reiser
* Lee Rene Levell
* Neal Alan Amann
* Sean Lyle Lease
* Otto Alan Alton
* Otto Alan Acton
* Otto Alan Aston
* Otto Alan Anton
* Eddie Rene Aden
* Lee Jamal Abell
* Andre Gene Adan
* Reed Alan Ahern
* Shane Pete Fast
* Elliot O Yokley
* Elliot O Soules
* Lee Pete Levell
* Ira Lamar Adair
* Neil Lyle Laine
* Teodoro Tom Ott
* Otto Adam Altom
* Noah Alan Amann
* Eddy Alan Alden
* Lee Jewel Ezell
* Cory Bob Abarca
* Andre Rene Adan
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Earle Gene Wren
* Dean Rory Ready
* Dana Bob Obando
* Luis Rory Reily
* Otto Asa Santos
* Eric Asa Rapier
* Gino Lyle Lange
* Eddy Alan Arden
* Kent Lyle Linke
* Andre Dewey Daw
* Eddie Les Eades
* Louie Pete Ault
* Eddie Jewel Dew
* Ian Reyes Ennis
* Edison O Rosier
* Ollie Lee Enloe
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Ira Jamar Adair
* Earle Rene Wren
* Ernie Dewey New
* Lee Jewel Ewell
* Eddie Wes Eades
* Drew Rory Reedy
* Al Isaias Arias
* Ollie Derek Lor
* Cary Bob Abarca
* Emile Gene Lien
* Arlie Dewey Law
* Ollie Dewey Low
* Rob Dewey Embry
* Curt Bob Abarca
* Earl Asa Laurel
* Stefan Asa Hess
* Eddie Reyes Dey
* Eli Dana Rapier
* Dane Bob Obando
* Elmo Rory Ramey
* Lee Jere Levell
* Ali Rufus Urias
* Emile Rene Lien
* Eddie Jere Eder
* Stan Lyle Lease
* Chi Derek Edick
* Earle Gene Oren
* Emile Gene Bien
* Earle Gene Uren
* Arturo Rory Tao
* Otis Asa Nation
* Genaro Rory Ngo
* Dane Lyle Linde
* Dane Lyle Lynde
* Dane Lyle Lunde
* Scot Lyle Loose
* Ali Reyes Elias
* Art Solomon Tam
* Donn Bob Obando
* Dino Bob Obando
* Andre Jewel Daw
* Neal Adan Amann
* Emile Rene Bien
* Otto Adan Alton
* Earle Rene Uren
* Otto Adan Acton
* Earle Rene Oren
* Otto Adan Anton
* Otto Adan Aston
* Dallas Asa Olds
* Erik Asa Rapier
* Reed Adan Ahern
* Ernie Jewel New
* Donn Lyle Linde
* Dino Lyle Linde
* Donn Lyle Lynde
* Dino Lyle Lunde
* Donn Lyle Lunde
* Dino Lyle Lynde
* Dong Bob Obando
* Teodoro Tod Ott
* Stefan Asa Bess
* Noah Adan Amann
* Arlie Jewel Law
* Issac Jc Ocasio
* Arlie Reyes Lay
* Ed Teodoro Ater
* Ollie Jewel Low
* Eddy Adan Alden
* Shad Lyle Lease
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Shon Lyle Loose
* Dong Lyle Lunde
* Ollie Reyes Loy
* Stefan Asa Ness
* Earle Dewey Rew
* Reed Asa Sayers
* Anibal Asa Dias
* Noe Reyes Edens
* Delmar Asa Olds
* Isreal Al Abril
* Isreal Al April
* Earle Reyes Rey
* Ernie Les Eanes
* Eddy Adan Arden
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Ernie Reyes Ney
* Morgan Asa Arms
* Olin Asa Nation
* Lou Solomon Ulm
* Ernie Wes Eanes
* Ernie Rey Edney
* Odis Asa Nation
* Murray Asa Arms
* Noe Reyes Evens
* Ollie Dee Enloe
* Leif Rory Reily
* Elmo Asa Raymer
* Isaiah Asa Sais
* Anibal Asa Bias
* Ollie Jere Flor
* Reed Asa Sagers
* Reed Asa Sauers
* Stefan Asa Vess
* Stefan Asa Jess
* Stefan Asa Gess
* Ezra Asa Laurel
* Erin Asa Rapier
* Emile Jere Mier
* Emile Jere Pier
* Emile Jere Bier
* Earle Jewel Rew
* Emile Jere Wier
* Emile Jere Kier
* Anibal Asa Sias
* Isaias Asa Sais
* Paris Asa Serpa
* Arlie Jere Klar
* Luigi Gil Ifill
* Hai Solomon Ihm
* Darell L Ilardi
* Chi Derek Emick
* Eddie Lee Emdee
* Daryl Al Ilardi
* Arlie Rey Emlay
* Eddie Rene Iden
* Chi Derek Enick
* Earle Rene Hren
* Trevor O Howeth
* Earle Gene Hren
* Duncan Asa Ends
* Danial Asa Ends
* Louie Pete Hult
* Eddie Gene Iden
* Chas Asa Kasack
* Clay Asa Kasack
* Lee Jewel Euell
* Chad Asa Kasack
* Ian Dana Katnik
* Chet Asa Kazeck
* Shane Pete Kast
* Leo Jewel Etoll
* Ian Dana Kamnik
* M Keenan Ingemi
* M Vernon Ingemi
* Ernie Jere Iner
* Eddie Dee Emdee
* Isaias Asa Kais
* Ed Steven Elsen
* Steve Pete Jest
* Isaiah Asa Kais
* Theron O Howeth
* Neil Asa Garing
* Ernie Wes Ennes
* Noah Asa Galang
* Shane Leo Eraso
* Steve Pete Gest
* Emile Jere Gier
* Israel E Gehrig
* N Eugene Genung
* Neal Asa Galang
* Elijah Asa Fies
* Steve Pete Fest
* Eli Peter Etier
* Ed Steven Essen
* Stefan Asa Fess
* Chi Derek Erick
* Ollie Pete Flot
* Earle Pete Fret
* Ernie Ben Ennen
* Emile Jere Hier
* Ernie Len Ennen
* Ernie Ken Ennen
* Theron O Horeth
* Trevor O Horeth
* Lee Bo Holowell
* Chi Derek Evick
* Ernie Les Ennes
* Adrian Asa Gras
* Earle Gene Gren
* Noe Reyes Ewens
* Ollie Jere Glor
* Shad Asa Habash
* Stan Asa Habash
* Earle Rene Gren
* Sean Asa Habash
* Aldo Alan Ardan
* Andy Adan Ardan
* Art Jamal Antal
* Aldo Adan Ardan
* Eli Jamal Ariel
* Elijah Al Ariel
* Andy Alan Ardan
* Dorian Asa Ards
* Leland N Analla
* R Keenan Andera
* Lee Jamal Amell
* Ty Isaiah Amith
* L Vernon Angela
* Antwan Al Antal
* R Vernon Andera
* L Keenan Angela
* Ed Isaias Aries
* Art Jamal Attal
* Elmo Adan Aumen
* Shane Peter Ast
* Antwan Al Attal
* Otto Alan Auton
* Isreal Al Avril
* Elmo Alan Aumen
* Otto Adan Auton
* Elmo Alan Armen
* Norman Asa Arns
* Isreal Asa Aris
* Elmo Adan Armen
* Alva Adan Arvan
* Alva Alan Arvan
* Otto Adan Arton
* Otto Alan Arton
* Otto Adan Afton
* Otto Alan Afton
* Eddie Jere Ader
* Duane Reyes Ady
* Isaias Adam Aid
* Isaias Adan Aid
* Isaiah Adam Aid
* Isaiah Adan Aid
* Lyle Bob Abella
* Blake Peter Abt
* Ira Jamar Abair
* Ira Lamar Abair
* Chase Reyes Acy
* Lee Jamal Adell
* Tobias Asa Abts
* Derick C Acorda
* Otto Adan Aiton
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Aron Adan Aloan
* Aron Alan Aloan
* Amos Adan Aloan
* Amos Alan Aloan
* Arlie Gene Alan
* Arlie Rene Alan
* Otto Alan Aiton
* Nigel Al Alagna
* Cecil Al Alecca
* Al Isaias Alias
* Arlie Jere Alar
* Bradly L Aldaba
* Arlie Jewell Aw
* Emile Jere Dier
* Elijah Asa Dies
* Emile Gene Dien
* Emile Rene Dien
* Rey Reyes Eayrs
* Roy Reyes Eayrs
* Les Dewey Easly
* Ray Reyes Eayrs
* Earl E Deserres
* Eddie Derek Der
* Earle Deserres
* Stefan Asa Dess
* Steve Pete Dest
* Ezra E Deserres
* Shelby Bob Deso
* Royce Les Eayrs
* Eddie Ben Elden
* Eddie Ken Elden
* Eddie Ken Eiden
* Eddie Len Eiden
* Chi Derek Elick
* Lee Solomon Elm
* Eddie Len Elden
* Ali Keven Elian
* Lee Jewel Edell
* Arlie Leo Edlao
* Royce Wes Eayrs
* Ed Steven Ebsen
* Al Steven Ehsan
* Eddie Ben Eiden
* Reuben Ed Efurd
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* Earle Rene Bren
* Robert Rory Bro
* L Rocco Cachola
* L Royce Cachola
* Royce Rene Byrn
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Otto Adan Axton
* Otto Alan Axton
* Adrian Asa Bras
* Earle Gene Bren
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Leo Gene Debold
* Leo Jere Debold
* Isaias Asa Dais
* Andre Derek Dar
* Leonel E Debold
* Lionel E Debold
* Leo Pete Debold
* Leo Rene Debold
* N Royce Cicconi
* Arlie Gene Clan
* N Boyce Cicconi
* N Rocco Cicconi
* Bruce Jere Cubr
* Isaiah Asa Dais
* Arlie Rene Clan
* Arlie Jere Clar
* Cleo Asa Kazeck
* Dean Rory Roady
* Ryan Rory Roary
* Ed Luigi Riller
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elwood O Rohwer
* Elmo Rory Romey
* Ed Luigi Rigler
* Deon Rory Rhody
* Dion Rory Rhody
* Eli Rene Revier
* Eliseo E Revier
* Ed Luigi Ridler
* Drew Rory Riedy
* Doug Rory Rhudy
* Anibal Asa Rias
* Dino Rory Rondy
* Ivan Asa Salais
* Silas Asa Salsa
* Isaiah a Salais
* Isaias a Salais
* Thomas a Sanots
* Troy Asa Sanots
* Alva Asa Salvas
* Denis Asa Sanda
* Ira Dana Salais
* Cesar Ira Rosca
* Drew Rory Ruedy
* Dong Rory Rondy
* Donn Rory Rondy
* Neil Asa Sabins
* Eloy Asa Sagoes
* Truman Asa Ruts
* Emery Ty Ryneer
* Eli Gene Regier
* Eli Jere Regier
* Ryan Rory Reary
* Ed Steve Reaser
* Eliseo E Regier
* Elmo Rory Remey
* Eli Pete Regier
* Eli Rene Regier
* Ezra Rory Rarey
* Dana Rory Randy
* Dane Rory Randy
* Art Dana Rajtar
* Elmo Asa Rammer
* Donn Rory Randy
* Earl Rory Rarey
* Dino Rory Randy
* Dong Rory Randy
* Eli Gene Renier
* Eddy E Resendes
* Stefan Asa Ress
* Ed Dee Resendes
* Eli Jere Revier
* Eli Pete Revier
* Alva Rory Revay
* Eli Gene Revier
* Eddie Resendes
* Eli Rene Renier
* Eliseo E Renier
* Eli Jere Renier
* Eli Pete Renier
* Art Pete Rentar
* Art Rene Rentar
* Art Gene Rentar
* Art Jere Rentar
* Alva Asa Sarvas
* Emmitt Ty Tomey
* Emmett Ty Tumey
* Emile Pete Tiet
* Emmett Ty Tomey
* Isaiah Asa Vais
* Isaias Asa Vais
* Emmitt Ty Tumey
* Benito Ty Tunby
* Emile Jere Tier
* T Dusty Tatsuta
* T Rusty Tatsuta
* Noe Dana Talent
* Noel Asa Talent
* Emile Gene Tien
* Emile Rene Tien
* Stefan Asa Tess
* Steve Pete Test
* E Otha Vanasten
* Elijah Asa Wies
* Isaiah Asa Zais
* Emile Gene Wien
* Emile Rene Wien
* Emile Rene Zien
* Emile Jere Zier
* Isaias Asa Zais
* Emile Gene Zien
* Stefan Asa Wess
* Emile Rene Vien
* Emile Jere Vier
* Anibal Asa Vias
* Emile Gene Vien
* N Mike Wedekind
* Neil E Wedekind
* Isaiah Asa Wais
* Isaias Asa Wais
* Ali Gene Setias
* Ali Jere Setias
* Noe Rene Serens
* Moses Asa Sesma
* Louis Asa Shula
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Noe Pete Serens
* Ezra Asa Sayres
* Rueben E Sebers
* Reed Asa Savers
* Earl Asa Sayres
* Noe Gene Serens
* Noe Jere Serens
* Miles Asa Selma
* Myles Asa Selma
* Emile Gene Sien
* Thad Asa Tabatt
* Tuan Asa Tabatt
* Ed Teodoro Ster
* Louie Pete Sult
* Duane Pete Tadt
* Graham Asa Tags
* Leo Dana Tabolt
* Leon Asa Tabolt
* Antwan Asa Stas
* Al Luigi Sillas
* Ed Luigi Sirles
* Emile Rene Sien
* Emile Jere Sier
* Louis Asa Soula
* Al Teodoro Star
* Ollie Pete Slot
* Edison O Solies
* Shelby Bob Leso
* Stefan Asa Less
* Tony Lyle Lente
* Zane Lyle Lenze
* Bret Lyle Liebe
* Elijah Asa Lies
* Anibal Asa Lias
* Robt Lyle Libre
* King Lyle Lenke
* Lee Dana Layell
* Eddy Lyle Ledee
* Arlie Keven Lav
* Lee Dana Lavell
* Lyle Lyle Lelle
* Kent Lyle Lenke
* Theo Lyle Leete
* Trey Lyle Leete
* Gene Lyle Longe
* Gino Lyle Lynge
* Isaiah Asa Mais
* Cecil Eli Lucci
* Gene Lyle Lynge
* I Otha Masaitis
* C Mike Mehelich
* Isaias Asa Mais
* Eddy a Marander
* Cecil Ali Lucci
* Daryl Eli Lordi
* Earl Lyle Loree
* Gino Lyle Longe
* Daryl Ali Lordi
* Ollie Peter Lot
* Paul Lyle Loupe
* Ezra Lyle Loree
* Gary Lyle Lorge
* Alvaro R Krivak
* Cletus U Kubeck
* W Rocky Knknown
* Adrian Asa Kras
* Duane Pete Ladt
* Isaiah Asa Lais
* Robt Lyle Labre
* Lee Dana Ladell
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Keenan Asa Keks
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Stefan Asa Kess
* Isaias Asa Lais
* Kurt Lyle Larke
* Vern Lyle Larve
* Kirk Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Lee Dana Lasell
* Shane Pete Last
* Karl Lyle Larke
* Dane Lyle Lande
* Dino Lyle Lande
* Elmo Asa Lammel
* Dana Lyle Lande
* Zane Lyle Lanze
* Dirk Lyle Larde
* Dong Lyle Lande
* Donn Lyle Lande
* Stefan Asa Mess
* Genaro R Orengo
* Isreal Asa Oris
* Otto Everett or
* Adrian Asa Oras
* Al Teodoro Otar
* Santo Coy Ounsy
* Morgan Asa Orms
* Murray Asa Orms
* Teodoro O Omoto
* Steve Pete Oest
* Emile Gene Oien
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Leo Solomon Olm
* Emile Rene Oien
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raemer
* Eddy Asa Raider
* Eddy Asa Radder
* Eddy Asa Raeder
* Isaias Asa Rais
* Antwan a Rajtar
* Elmo Asa Raimer
* Isaiah Asa Rais
* Adrian Adan Rad
* Isaias Asa Pais
* Elijah Asa Pies
* Ollie Jewell Ow
* Isaiah Asa Pais
* Rupert Rory Pro
* Adrian Adam Rad
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Isaias a Narain
* Ivan Asa Narain
* Steve Pete Nest
* Ernie Peter Net
* Ed Steve Neisen
* Ed Steve Nessen
* Isaiah a Narain
* Shannon Z Naasz
* Odis Asa Nacion
* Anibal Asa Mias
* Al Luigi Millam
* Otto Asa Nanton
* Ira Dana Narain
* Olin Asa Nacion
* Otis Asa Nacion
* Ernie Keven Nev
* L Damon Odonald
* L Daron Odonald
* L Aaron Odonald
* L Carol Odonald
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* L Jarod Odonald
* Eddie Jere Oder
* Austin I Nissan
* Elliot O Nowlen
* Emile Jere Nier
* Ian Solomon Nim
* Neal Bob Obiano
* Noah Bob Obiano
* Elroy Ty Nygren
* Emery Ty Nyreen
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5733 "glurk"] (non-homophonic solutions) ==
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Angelo Lyle Gay
* Andre Reyes Day
* Shane Pete Mast
* Shane Pete Fast
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Dean Rory Ready
* Luis Rory Reily
* Gino Lyle Lange
* Louie Pete Ault
* Edison O Rosier
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Arlie Dewey Law
* Rob Dewey Embry
* Eli Dana Rapier
* Elmo Rory Ramey
* Ali Rufus Urias
* Chi Derek Edick
* Otis Asa Nation
* Ali Reyes Elias
* Art Solomon Tam
* Andre Jewel Daw
* Dino Lyle Linde
* Dino Lyle Lunde
* Dino Lyle Lynde
* Arlie Reyes Lay
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Dong Lyle Lunde
* Delmar Asa Olds
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Odis Asa Nation
* Leif Rory Reily
* Elmo Asa Raymer
* Hai Solomon Ihm
* Chi Derek Emick
* Daryl Al Ilardi
* Arlie Rey Emlay
* Chi Derek Enick
* Trevor O Howeth
* Louie Pete Hult
* Chet Asa Kazeck
* Shane Pete Kast
* M Vernon Ingemi
* Neil Asa Garing
* Shane Leo Eraso
* Israel E Gehrig
* Elijah Asa Fies
* Chi Derek Erick
* Trevor O Horeth
* Chi Derek Evick
* L Vernon Angela
* Elmo Adan Aumen
* Shane Peter Ast
* Elmo Alan Aumen
* Elmo Alan Armen
* Elmo Adan Armen
* Duane Reyes Ady
* Blake Peter Abt
* Chase Reyes Acy
* Derick C Acorda
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Elijah Asa Dies
* Shelby Bob Deso
* Royce Les Eayrs
* Chi Derek Elick
* Ali Keven Elian
* Royce Wes Eayrs
* Al Steven Ehsan
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* L Royce Cachola
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Arlie Gene Clan
* Arlie Rene Clan
* Cleo Asa Kazeck
* Dean Rory Roady
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elmo Rory Romey
* Ed Luigi Rigler
* Ed Luigi Ridler
* Doug Rory Rhudy
* Dino Rory Rondy
* Dong Rory Rondy
* Truman Asa Ruts
* Dana Rory Randy
* Dane Rory Randy
* Dino Rory Randy
* Dong Rory Randy
* Benito Ty Tunby
* Noel Asa Talent
* E Otha Vanasten
* Elijah Asa Wies
* N Mike Wedekind
* Ali Gene Setias
* Ali Jere Setias
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Louie Pete Sult
* Leo Dana Tabolt
* Leon Asa Tabolt
* Ed Luigi Sirles
* Al Teodoro Star
* Shelby Bob Leso
* Elijah Asa Lies
* Robt Lyle Libre
* Arlie Keven Lav
* Gino Lyle Lynge
* C Mike Mehelich
* Daryl Eli Lordi
* Gino Lyle Longe
* Daryl Ali Lordi
* Gary Lyle Lorge
* Cletus U Kubeck
* Duane Pete Ladt
* Robt Lyle Labre
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Kurt Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Shane Pete Last
* Dino Lyle Lande
* Dana Lyle Lande
* Dirk Lyle Larde
* Dong Lyle Lande
* Santo Coy Ounsy
* Morgan Asa Orms
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raimer
* Elijah Asa Pies
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Odis Asa Nacion
* Otis Asa Nacion
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* Elroy Ty Nygren
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5676 "PBFred"] ==
* Evil Anal Aziel
== From doranchak [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=30#p22403 (1)] [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=40#p22438 (2)]==
* A McNamara Scar
* Ate severed ear
* Trove Behemoth
* Spiro Motorist
* Laura Catapult
* Alice Venetian
* Agile Venetian
* Lebanon Enable
* Indiana Saudis
* Extras Adopted
* Athlete Lethal
* Achieve Lethal
* a Fine Venetian
* of Flanagan Fog
* to One Behemoth
* Extras Adapted
* Training Neat
* Chinese Eel Ice
* Artists Use Tau
* Our Bananas Ron
* Its Revered Sir
* Our Faraway Row
* Old Bikinis Don
* Of These Men Tom (or Of The Semen Tom)
* Greats To The Go
* Or I Was A Nation
* O He Was A Face Of
* [http://www.zodiackillerciphers.com/?p=152 Over 2,700 phrases from Project Gutenberg experiment]
* [https://docs.google.com/spreadsheets/d/13R16xILq6XIWTklErwZq7ltod7EG08-zeiG0AnAtsl4/edit?usp=sharing Another Project Gutenberg experiment, scanned 61.5 GB of text]
* [http://www.zodiackillerciphers.com/?p=467 From article], person names:
** Chastity Tracy
** Erica Natalie T
** Islami M Amelia
** Eddie Resendes
** Ernie Zerenner
** Aileen Enerlan
** Chitumu Eunice
** Ariyana Mariam
** Sripada Harish
** Ali Raja Mariam
** Arriaga Laura L
** Duitama David D
** Steve Menezes N
** Arriaza Laura L
** Arizala Maria M
** Adriana Laura L
** Aziz a Zahaniah
* [http://www.zodiackillerciphers.com/?p=467 From article], phrases / word combinations:
** Sarah The Horse
** Uncle Peter Cut
** Achieve Lethal
** Obscene Nelson
** Extreme Reuter
** Emperors Ropes
** Leigh The Haile
** Kane Pops Punks
** Gareth Tot Ergo
** Niece Gene Penn
** Drop Rarer Code
** Door Non-Encode
** Iraq Alan Again
** All Banana Alan
** Alice Venetian
** Laura Catapult
** Afghan Amalgam
** Reassess Scars
** Clara Cataract
** Shannon Encase
** Okinawa Nation
** Indiana Saudis
** Regan Adalard
** Drippy Peptide
** Outlet Erector
** Akira Canadian
** Adriana Marram
** Mary Nina Norma
** Robert Rory Bro
** Smile Pete List
** Mary Tate Terme
** Mary Gags Germs
** Ryan Amaya Gary
** Daniel Eye Andy
** Eats Bobs Bates
** Kill Baby Bulky
** Shit Pipe Poise
** Eric Alan Alien
** Slave Pete Last
** Extra War After
** Murder Eye Army
** Clara Fatal Act
** Encoded Odd CEO
** [http://zodiackillerciphers.com/z13wordsearch-results-2-sorted.txt List of 283 phrases / word combinations that use two words]
** [http://zodiackillerciphers.com/z13wordsearch-results-3-sorted.txt List of 1,283,443 phrases / word combinations that use three words]
* From another corpus test for [https://www.reddit.com/r/ZodiacKiller/comments/axqx4z/z13_my_name_is_cipher/ reddit post]:
** Chief of Africa
** Uncle Peter Cut
** of Hair It Is Hot
** of These Newton
** at Me O Son of Man
** a Wide Venetian
** a Ripe Venetian
** Avis, a Canadian
** India. Was, and Is.
** I Saw Alan Again
** I Was a Man Again
** I Had a Man Again
** Near a Way As Any
** Claus Asks Jack
** Guest at Otsego
** One Has a Name on
** One Had an Axe on
** As if a Canadian
** Oh No It It Is Not
** Is That As Art Is
** Nearer Eden and
** Niagara Day And
** [http://zodiackillerciphers.com/z13-corpus-solutions.txt Full unprocessed results]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4305&p=69616 More results from corpus scanning:]
** So I'm a Satanist
** So I'm a Fatalist (from glurk)
** A Dog, a Cat, a Goat
** or Steve Nelson
** As I Had an Asian
** a Kid: a Canadian
** Emperor's Ropes
** As Real As Auras
** That I Die, I Hate
** One Has a Name on
** I've Had an Axe in
** Spectate These
** if I Was a Nazi in
** I Eat a Banana in
** As I'm a Canadian
** I Was a Canadian
** Leave Helen All
** Edit As an Alien
** Shakalaka Mask
** Shit! a Natalist!
** Shit! a Fatalist!
** Shit! a Satanist!
** Is a Pagan Again
** Extra Caracter
** and Gamal Abdal
** Donut. It Stands.
** Al Is a Canadian
** Reign on Entire
** I've Had a Dane I.D.
** Least It Steals
** Ratio, Do You Try?
** Said As a Taoist

== From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6406 "Deryk"] ==
* Male, Initial: M.T.
== From [https://www.tapatalk.com/groups/zodiackillerfr/my-name-is-zodiac-t2276-s20.html#p139086 "MickCal"] ==
* OL STEVE NELSON
== From [https://discord.com/channels/996952324150931477/996952376894292018/1135335122527342604 "Toad"] ==
* AMIGO COLONIAL
== From [https://discord.com/channels/996952324150931477/996952376894292018/1033254655381217320 "Antisquid42"] ==
* John E. Heresh Jr.
* Donald LeLinde
* Neal O’Donovann
* Doug Lyle Laude
* Chip O. Kozowicz
* Seth Everett Sr.
* Andrew E. Levdal
* Paul Lyle Loupe
* Shiloh Oto List
* Juan O. Corona Jr.
* Frank X. LeLoafe
* Leo Solomon Olm
== From [http://zodiackillerciphers.com/z13_2_word_solutions.txt "rando"] ==
* [http://zodiackillerciphers.com/z13_2_word_solutions.txt 3,142 2-word solutions]

== Partial solution from [http://zodiackiller.21.forumer.com/viewtopic.php?p=119889#119889 "granny101"] ==
* ILLNEVETELLIT ("I'LL NEVER TELL IT", with the "R" missing)

= Solutions that fit if you first reverse the cipher =

TODO

= Solutions that fit the ciphertext if you permit anagramming =

Rearranging the cipher text significantly reduces the constraints on possible solutions. As [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=20#p13716 "glurk"] points out, anagramming the 13 symbols permits a very large variety of possible solutions, which makes it nearly impossible to validate any given solution derived this way.

Here are some examples of solutions that arise from anagramming:

* [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=40#p13807 Small sampling from "sincos"]
* From doranchak:
** 13-letter English words that have the same letter distribution as the symbols of the cipher:
*** international, participation, concentration, interventions, investigating, participating, inappropriate, investigative, authoritarian, mediterranean, intentionally, accommodation, strengthening, commissioners, differentiate, collaborators, incorporation, unwillingness, mismanagement, superstitious, mathematician, nationalities, instantaneous, nationalistic, inconsistency, choreographer, preponderance, condescending, applicability, contingencies, indeterminate, sarcastically, temperamental, disillusioned, prerequisites, intelligences, irreplaceable, headquartered, reincarnation, proportionate, appropriating, inclusiveness, preservatives, ornamentation, uninteresting, incapacitated, contaminating, irrationality, abolitionists, improprieties, structuralist, sharecroppers, solicitations, intermarriage, arbitrariness, impermissible, disconnection, professorship, scintillating, insufficiency, spectroscopic, satisfactions
** Small sampling of 13-letter surnames that have the same letter distribution as the symbols of the cipher:
*** radhakrishnan, bhattacharjee, villavicencio, chattopadhyay, oluwatobiloba, degraffenreid, knappenberger, brandenburger, hebblethwaite, rathakrishnan, degraffenried, sahasrabuddhe, stamatopoulos, schlegelmilch, sastrowardoyo, konstantinova, muruganantham, thorsteinsson, madhusoodanan, wojciechowicz, hintermeister, klingenberger, vansteenkiste, raveendranath, blankenbiller, messerschmitt, abdollahzadeh, vlaisavljevic, stamatopoulou, giacomantonio, gebregziabher, gardarsdottir, blattenberger, agustiningsih, sverrisdottir, shirmohammadi, reichenbacher, schottenstein, christophoros, javakhishvili, sundareswaran, schiermeister, kaluhiokalani, natsvlishvili, monteferrante, ntakirutimana, derakhshandeh, winternheimer, spangenberger, liechtenstein, heiderscheidt, chandrarathne, shettlesworth
** [http://zodiackillerciphers.com/all-names-z13-list2-sorted.txt A sampling of 69,607 common first-last name combinations] that have the same letter distribution as the symbols of the cipher.
*** [http://zodiackillersite.com/viewtopic.php?p=18552#p18552 (Original broken forum link)]
* From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6376 Tom Voigt]:
** knickerbocker
** [http://zodiackiller.21.forumer.com/viewtopic.php?p=120299#120299 aintgonnatell]
* From [http://www.santarosahitchhikermurders.com/ Deb Silva]:
** [http://en.wikipedia.org/wiki/Bobby_Beausoleil Bob Beausoleil]
* From Anonymous:
** Jimmy Phillips (also credited to [http://zodiackiller.fr.yuku.com/topic/3827/Jimmy-Phillips alanbenjy])
* From Christer Böke:
** Frank Frazetta ([http://zodiackillersite.com/viewtopic.php?f=63&t=1275 Tim Holt] was drawn by Frank Bollle and Frank Frazetta)
** Grant Santiago
* From [https://www.tapatalk.com/groups/zodiackillerfr/simple-solve-for-the-my-name-is-t8738.html#p145360 jaydeezodiachunter]:
** Debbie Faraday

= Solutions that fit if you relax other constraints of the cipher =

Solutions that fit if you allow all three "circled 8" symbols to be wildcards:
* From Michael Kelleher:
** thebigsecrete
Solutions that are produced via multiple operations:
* From [http://www.zodiackillerciphers.com/?p=46 Lyndon Lafferty]:
** NAME GRANT, or NAME IS GRANT
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/detailed-solution-to-z13-and-z32/ Faycal Ziraoui's solution]
A solution that applies the 408 key and interprets some symbols as nulls:
* from [http://zodiackiller.fr.yuku.com/topic/6839/Zodiacs-Name-using-408-Key Rembrandt]:
** ED SHAW
Solutions with one name part in the middle, and another name part split in half and written backwards:
* [http://www.zodiackillersite.com/viewtopic.php?p=69126#p69126 DEBBIE FARADAY]

= Other interpretations =

* "My name is" contains 8 letters. The cipher text contains 8 letters and 5 special symbols. The special symbols contain Zodiac's name and the rest just mean "My name is" (Source: Jeppesen)
* [https://www.tapatalk.com/groups/zodiackillerfr/general-book-discussion-for-hunted-the-zodiac-murd-t10141.html#p197345 "Set addition" interpretation of Z13 by Doug Oswell], resulting in solution: "FROM TED KACZYNS[K]I"
* [https://www.tapatalk.com/groups/zodiackillerfr/paul-astrup-s-theory-meteorological-symbols-challe-t10261.html#p202558 Weather symbols]
* The line after "My name is" is roughly above symbols that resemble "Tom" spelled backwards. (Source: David Cauley via YouTube comments)

Z13 Solutions

2024-01-03T16:57:49Z

Admin: /* From "Antisquid42" */

= Solutions that fit the ciphertext as is =

This section only shows proposed solutions that fit the cipher text "as is". No anagramming or other re-arrangements are used here, and the cipher is considered to be strictly a substitution cipher. Solutions that permit anagramming are very easy to come by, as there are several billion possible string combinations to choose from. Solutions that do not require anagramming are still numerous, however, which increases the difficulty of knowing which one is correct.

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=50&t=1390&p=24191#p24190 "Quill"] ==
* Eddie Penerden
* Stan T E Case (using "8"s as spaces)
* Greg N A Vega (using "8"s as spaces)

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5677 "glurk"] (homophonic solutions) ==
* Steve Pete West
* Adrian a Harrah
* Shannon E Nease
* Steve Pete Best
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Eddie Gene Oden
* Steve Pete Vest
* Barney E Yearby
* Gene Lyle Lange
* Eddie Gene Eden
* Ed Steven Eisen
* E Alva Vanallen
* Angelo Lyle Gay
* Eddie Rene Oden
* Isreal a Sarris
* Carl Bob Abarca
* Elliot O Roller
* Andre Reyes Day
* Ed Steve Nelsen
* Shane Pete East
* Lee Gene Levell
* Eddie Rene Eden
* Rueben E Segers
* Rueben E Severs
* Eddie Gene Aden
* Eddie Dewey Dew
* Shane Pete Mast
* Ed Steve Reeser
* Ed Steve Reiser
* Lee Rene Levell
* Neal Alan Amann
* Sean Lyle Lease
* Otto Alan Alton
* Otto Alan Acton
* Otto Alan Aston
* Otto Alan Anton
* Eddie Rene Aden
* Lee Jamal Abell
* Andre Gene Adan
* Reed Alan Ahern
* Shane Pete Fast
* Elliot O Yokley
* Elliot O Soules
* Lee Pete Levell
* Ira Lamar Adair
* Neil Lyle Laine
* Teodoro Tom Ott
* Otto Adam Altom
* Noah Alan Amann
* Eddy Alan Alden
* Lee Jewel Ezell
* Cory Bob Abarca
* Andre Rene Adan
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Earle Gene Wren
* Dean Rory Ready
* Dana Bob Obando
* Luis Rory Reily
* Otto Asa Santos
* Eric Asa Rapier
* Gino Lyle Lange
* Eddy Alan Arden
* Kent Lyle Linke
* Andre Dewey Daw
* Eddie Les Eades
* Louie Pete Ault
* Eddie Jewel Dew
* Ian Reyes Ennis
* Edison O Rosier
* Ollie Lee Enloe
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Ira Jamar Adair
* Earle Rene Wren
* Ernie Dewey New
* Lee Jewel Ewell
* Eddie Wes Eades
* Drew Rory Reedy
* Al Isaias Arias
* Ollie Derek Lor
* Cary Bob Abarca
* Emile Gene Lien
* Arlie Dewey Law
* Ollie Dewey Low
* Rob Dewey Embry
* Curt Bob Abarca
* Earl Asa Laurel
* Stefan Asa Hess
* Eddie Reyes Dey
* Eli Dana Rapier
* Dane Bob Obando
* Elmo Rory Ramey
* Lee Jere Levell
* Ali Rufus Urias
* Emile Rene Lien
* Eddie Jere Eder
* Stan Lyle Lease
* Chi Derek Edick
* Earle Gene Oren
* Emile Gene Bien
* Earle Gene Uren
* Arturo Rory Tao
* Otis Asa Nation
* Genaro Rory Ngo
* Dane Lyle Linde
* Dane Lyle Lynde
* Dane Lyle Lunde
* Scot Lyle Loose
* Ali Reyes Elias
* Art Solomon Tam
* Donn Bob Obando
* Dino Bob Obando
* Andre Jewel Daw
* Neal Adan Amann
* Emile Rene Bien
* Otto Adan Alton
* Earle Rene Uren
* Otto Adan Acton
* Earle Rene Oren
* Otto Adan Anton
* Otto Adan Aston
* Dallas Asa Olds
* Erik Asa Rapier
* Reed Adan Ahern
* Ernie Jewel New
* Donn Lyle Linde
* Dino Lyle Linde
* Donn Lyle Lynde
* Dino Lyle Lunde
* Donn Lyle Lunde
* Dino Lyle Lynde
* Dong Bob Obando
* Teodoro Tod Ott
* Stefan Asa Bess
* Noah Adan Amann
* Arlie Jewel Law
* Issac Jc Ocasio
* Arlie Reyes Lay
* Ed Teodoro Ater
* Ollie Jewel Low
* Eddy Adan Alden
* Shad Lyle Lease
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Shon Lyle Loose
* Dong Lyle Lunde
* Ollie Reyes Loy
* Stefan Asa Ness
* Earle Dewey Rew
* Reed Asa Sayers
* Anibal Asa Dias
* Noe Reyes Edens
* Delmar Asa Olds
* Isreal Al Abril
* Isreal Al April
* Earle Reyes Rey
* Ernie Les Eanes
* Eddy Adan Arden
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Ernie Reyes Ney
* Morgan Asa Arms
* Olin Asa Nation
* Lou Solomon Ulm
* Ernie Wes Eanes
* Ernie Rey Edney
* Odis Asa Nation
* Murray Asa Arms
* Noe Reyes Evens
* Ollie Dee Enloe
* Leif Rory Reily
* Elmo Asa Raymer
* Isaiah Asa Sais
* Anibal Asa Bias
* Ollie Jere Flor
* Reed Asa Sagers
* Reed Asa Sauers
* Stefan Asa Vess
* Stefan Asa Jess
* Stefan Asa Gess
* Ezra Asa Laurel
* Erin Asa Rapier
* Emile Jere Mier
* Emile Jere Pier
* Emile Jere Bier
* Earle Jewel Rew
* Emile Jere Wier
* Emile Jere Kier
* Anibal Asa Sias
* Isaias Asa Sais
* Paris Asa Serpa
* Arlie Jere Klar
* Luigi Gil Ifill
* Hai Solomon Ihm
* Darell L Ilardi
* Chi Derek Emick
* Eddie Lee Emdee
* Daryl Al Ilardi
* Arlie Rey Emlay
* Eddie Rene Iden
* Chi Derek Enick
* Earle Rene Hren
* Trevor O Howeth
* Earle Gene Hren
* Duncan Asa Ends
* Danial Asa Ends
* Louie Pete Hult
* Eddie Gene Iden
* Chas Asa Kasack
* Clay Asa Kasack
* Lee Jewel Euell
* Chad Asa Kasack
* Ian Dana Katnik
* Chet Asa Kazeck
* Shane Pete Kast
* Leo Jewel Etoll
* Ian Dana Kamnik
* M Keenan Ingemi
* M Vernon Ingemi
* Ernie Jere Iner
* Eddie Dee Emdee
* Isaias Asa Kais
* Ed Steven Elsen
* Steve Pete Jest
* Isaiah Asa Kais
* Theron O Howeth
* Neil Asa Garing
* Ernie Wes Ennes
* Noah Asa Galang
* Shane Leo Eraso
* Steve Pete Gest
* Emile Jere Gier
* Israel E Gehrig
* N Eugene Genung
* Neal Asa Galang
* Elijah Asa Fies
* Steve Pete Fest
* Eli Peter Etier
* Ed Steven Essen
* Stefan Asa Fess
* Chi Derek Erick
* Ollie Pete Flot
* Earle Pete Fret
* Ernie Ben Ennen
* Emile Jere Hier
* Ernie Len Ennen
* Ernie Ken Ennen
* Theron O Horeth
* Trevor O Horeth
* Lee Bo Holowell
* Chi Derek Evick
* Ernie Les Ennes
* Adrian Asa Gras
* Earle Gene Gren
* Noe Reyes Ewens
* Ollie Jere Glor
* Shad Asa Habash
* Stan Asa Habash
* Earle Rene Gren
* Sean Asa Habash
* Aldo Alan Ardan
* Andy Adan Ardan
* Art Jamal Antal
* Aldo Adan Ardan
* Eli Jamal Ariel
* Elijah Al Ariel
* Andy Alan Ardan
* Dorian Asa Ards
* Leland N Analla
* R Keenan Andera
* Lee Jamal Amell
* Ty Isaiah Amith
* L Vernon Angela
* Antwan Al Antal
* R Vernon Andera
* L Keenan Angela
* Ed Isaias Aries
* Art Jamal Attal
* Elmo Adan Aumen
* Shane Peter Ast
* Antwan Al Attal
* Otto Alan Auton
* Isreal Al Avril
* Elmo Alan Aumen
* Otto Adan Auton
* Elmo Alan Armen
* Norman Asa Arns
* Isreal Asa Aris
* Elmo Adan Armen
* Alva Adan Arvan
* Alva Alan Arvan
* Otto Adan Arton
* Otto Alan Arton
* Otto Adan Afton
* Otto Alan Afton
* Eddie Jere Ader
* Duane Reyes Ady
* Isaias Adam Aid
* Isaias Adan Aid
* Isaiah Adam Aid
* Isaiah Adan Aid
* Lyle Bob Abella
* Blake Peter Abt
* Ira Jamar Abair
* Ira Lamar Abair
* Chase Reyes Acy
* Lee Jamal Adell
* Tobias Asa Abts
* Derick C Acorda
* Otto Adan Aiton
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Aron Adan Aloan
* Aron Alan Aloan
* Amos Adan Aloan
* Amos Alan Aloan
* Arlie Gene Alan
* Arlie Rene Alan
* Otto Alan Aiton
* Nigel Al Alagna
* Cecil Al Alecca
* Al Isaias Alias
* Arlie Jere Alar
* Bradly L Aldaba
* Arlie Jewell Aw
* Emile Jere Dier
* Elijah Asa Dies
* Emile Gene Dien
* Emile Rene Dien
* Rey Reyes Eayrs
* Roy Reyes Eayrs
* Les Dewey Easly
* Ray Reyes Eayrs
* Earl E Deserres
* Eddie Derek Der
* Earle Deserres
* Stefan Asa Dess
* Steve Pete Dest
* Ezra E Deserres
* Shelby Bob Deso
* Royce Les Eayrs
* Eddie Ben Elden
* Eddie Ken Elden
* Eddie Ken Eiden
* Eddie Len Eiden
* Chi Derek Elick
* Lee Solomon Elm
* Eddie Len Elden
* Ali Keven Elian
* Lee Jewel Edell
* Arlie Leo Edlao
* Royce Wes Eayrs
* Ed Steven Ebsen
* Al Steven Ehsan
* Eddie Ben Eiden
* Reuben Ed Efurd
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* Earle Rene Bren
* Robert Rory Bro
* L Rocco Cachola
* L Royce Cachola
* Royce Rene Byrn
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Otto Adan Axton
* Otto Alan Axton
* Adrian Asa Bras
* Earle Gene Bren
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Leo Gene Debold
* Leo Jere Debold
* Isaias Asa Dais
* Andre Derek Dar
* Leonel E Debold
* Lionel E Debold
* Leo Pete Debold
* Leo Rene Debold
* N Royce Cicconi
* Arlie Gene Clan
* N Boyce Cicconi
* N Rocco Cicconi
* Bruce Jere Cubr
* Isaiah Asa Dais
* Arlie Rene Clan
* Arlie Jere Clar
* Cleo Asa Kazeck
* Dean Rory Roady
* Ryan Rory Roary
* Ed Luigi Riller
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elwood O Rohwer
* Elmo Rory Romey
* Ed Luigi Rigler
* Deon Rory Rhody
* Dion Rory Rhody
* Eli Rene Revier
* Eliseo E Revier
* Ed Luigi Ridler
* Drew Rory Riedy
* Doug Rory Rhudy
* Anibal Asa Rias
* Dino Rory Rondy
* Ivan Asa Salais
* Silas Asa Salsa
* Isaiah a Salais
* Isaias a Salais
* Thomas a Sanots
* Troy Asa Sanots
* Alva Asa Salvas
* Denis Asa Sanda
* Ira Dana Salais
* Cesar Ira Rosca
* Drew Rory Ruedy
* Dong Rory Rondy
* Donn Rory Rondy
* Neil Asa Sabins
* Eloy Asa Sagoes
* Truman Asa Ruts
* Emery Ty Ryneer
* Eli Gene Regier
* Eli Jere Regier
* Ryan Rory Reary
* Ed Steve Reaser
* Eliseo E Regier
* Elmo Rory Remey
* Eli Pete Regier
* Eli Rene Regier
* Ezra Rory Rarey
* Dana Rory Randy
* Dane Rory Randy
* Art Dana Rajtar
* Elmo Asa Rammer
* Donn Rory Randy
* Earl Rory Rarey
* Dino Rory Randy
* Dong Rory Randy
* Eli Gene Renier
* Eddy E Resendes
* Stefan Asa Ress
* Ed Dee Resendes
* Eli Jere Revier
* Eli Pete Revier
* Alva Rory Revay
* Eli Gene Revier
* Eddie Resendes
* Eli Rene Renier
* Eliseo E Renier
* Eli Jere Renier
* Eli Pete Renier
* Art Pete Rentar
* Art Rene Rentar
* Art Gene Rentar
* Art Jere Rentar
* Alva Asa Sarvas
* Emmitt Ty Tomey
* Emmett Ty Tumey
* Emile Pete Tiet
* Emmett Ty Tomey
* Isaiah Asa Vais
* Isaias Asa Vais
* Emmitt Ty Tumey
* Benito Ty Tunby
* Emile Jere Tier
* T Dusty Tatsuta
* T Rusty Tatsuta
* Noe Dana Talent
* Noel Asa Talent
* Emile Gene Tien
* Emile Rene Tien
* Stefan Asa Tess
* Steve Pete Test
* E Otha Vanasten
* Elijah Asa Wies
* Isaiah Asa Zais
* Emile Gene Wien
* Emile Rene Wien
* Emile Rene Zien
* Emile Jere Zier
* Isaias Asa Zais
* Emile Gene Zien
* Stefan Asa Wess
* Emile Rene Vien
* Emile Jere Vier
* Anibal Asa Vias
* Emile Gene Vien
* N Mike Wedekind
* Neil E Wedekind
* Isaiah Asa Wais
* Isaias Asa Wais
* Ali Gene Setias
* Ali Jere Setias
* Noe Rene Serens
* Moses Asa Sesma
* Louis Asa Shula
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Noe Pete Serens
* Ezra Asa Sayres
* Rueben E Sebers
* Reed Asa Savers
* Earl Asa Sayres
* Noe Gene Serens
* Noe Jere Serens
* Miles Asa Selma
* Myles Asa Selma
* Emile Gene Sien
* Thad Asa Tabatt
* Tuan Asa Tabatt
* Ed Teodoro Ster
* Louie Pete Sult
* Duane Pete Tadt
* Graham Asa Tags
* Leo Dana Tabolt
* Leon Asa Tabolt
* Antwan Asa Stas
* Al Luigi Sillas
* Ed Luigi Sirles
* Emile Rene Sien
* Emile Jere Sier
* Louis Asa Soula
* Al Teodoro Star
* Ollie Pete Slot
* Edison O Solies
* Shelby Bob Leso
* Stefan Asa Less
* Tony Lyle Lente
* Zane Lyle Lenze
* Bret Lyle Liebe
* Elijah Asa Lies
* Anibal Asa Lias
* Robt Lyle Libre
* King Lyle Lenke
* Lee Dana Layell
* Eddy Lyle Ledee
* Arlie Keven Lav
* Lee Dana Lavell
* Lyle Lyle Lelle
* Kent Lyle Lenke
* Theo Lyle Leete
* Trey Lyle Leete
* Gene Lyle Longe
* Gino Lyle Lynge
* Isaiah Asa Mais
* Cecil Eli Lucci
* Gene Lyle Lynge
* I Otha Masaitis
* C Mike Mehelich
* Isaias Asa Mais
* Eddy a Marander
* Cecil Ali Lucci
* Daryl Eli Lordi
* Earl Lyle Loree
* Gino Lyle Longe
* Daryl Ali Lordi
* Ollie Peter Lot
* Paul Lyle Loupe
* Ezra Lyle Loree
* Gary Lyle Lorge
* Alvaro R Krivak
* Cletus U Kubeck
* W Rocky Knknown
* Adrian Asa Kras
* Duane Pete Ladt
* Isaiah Asa Lais
* Robt Lyle Labre
* Lee Dana Ladell
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Keenan Asa Keks
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Stefan Asa Kess
* Isaias Asa Lais
* Kurt Lyle Larke
* Vern Lyle Larve
* Kirk Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Lee Dana Lasell
* Shane Pete Last
* Karl Lyle Larke
* Dane Lyle Lande
* Dino Lyle Lande
* Elmo Asa Lammel
* Dana Lyle Lande
* Zane Lyle Lanze
* Dirk Lyle Larde
* Dong Lyle Lande
* Donn Lyle Lande
* Stefan Asa Mess
* Genaro R Orengo
* Isreal Asa Oris
* Otto Everett or
* Adrian Asa Oras
* Al Teodoro Otar
* Santo Coy Ounsy
* Morgan Asa Orms
* Murray Asa Orms
* Teodoro O Omoto
* Steve Pete Oest
* Emile Gene Oien
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Leo Solomon Olm
* Emile Rene Oien
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raemer
* Eddy Asa Raider
* Eddy Asa Radder
* Eddy Asa Raeder
* Isaias Asa Rais
* Antwan a Rajtar
* Elmo Asa Raimer
* Isaiah Asa Rais
* Adrian Adan Rad
* Isaias Asa Pais
* Elijah Asa Pies
* Ollie Jewell Ow
* Isaiah Asa Pais
* Rupert Rory Pro
* Adrian Adam Rad
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Isaias a Narain
* Ivan Asa Narain
* Steve Pete Nest
* Ernie Peter Net
* Ed Steve Neisen
* Ed Steve Nessen
* Isaiah a Narain
* Shannon Z Naasz
* Odis Asa Nacion
* Anibal Asa Mias
* Al Luigi Millam
* Otto Asa Nanton
* Ira Dana Narain
* Olin Asa Nacion
* Otis Asa Nacion
* Ernie Keven Nev
* L Damon Odonald
* L Daron Odonald
* L Aaron Odonald
* L Carol Odonald
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* L Jarod Odonald
* Eddie Jere Oder
* Austin I Nissan
* Elliot O Nowlen
* Emile Jere Nier
* Ian Solomon Nim
* Neal Bob Obiano
* Noah Bob Obiano
* Elroy Ty Nygren
* Emery Ty Nyreen
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5733 "glurk"] (non-homophonic solutions) ==
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Angelo Lyle Gay
* Andre Reyes Day
* Shane Pete Mast
* Shane Pete Fast
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Dean Rory Ready
* Luis Rory Reily
* Gino Lyle Lange
* Louie Pete Ault
* Edison O Rosier
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Arlie Dewey Law
* Rob Dewey Embry
* Eli Dana Rapier
* Elmo Rory Ramey
* Ali Rufus Urias
* Chi Derek Edick
* Otis Asa Nation
* Ali Reyes Elias
* Art Solomon Tam
* Andre Jewel Daw
* Dino Lyle Linde
* Dino Lyle Lunde
* Dino Lyle Lynde
* Arlie Reyes Lay
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Dong Lyle Lunde
* Delmar Asa Olds
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Odis Asa Nation
* Leif Rory Reily
* Elmo Asa Raymer
* Hai Solomon Ihm
* Chi Derek Emick
* Daryl Al Ilardi
* Arlie Rey Emlay
* Chi Derek Enick
* Trevor O Howeth
* Louie Pete Hult
* Chet Asa Kazeck
* Shane Pete Kast
* M Vernon Ingemi
* Neil Asa Garing
* Shane Leo Eraso
* Israel E Gehrig
* Elijah Asa Fies
* Chi Derek Erick
* Trevor O Horeth
* Chi Derek Evick
* L Vernon Angela
* Elmo Adan Aumen
* Shane Peter Ast
* Elmo Alan Aumen
* Elmo Alan Armen
* Elmo Adan Armen
* Duane Reyes Ady
* Blake Peter Abt
* Chase Reyes Acy
* Derick C Acorda
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Elijah Asa Dies
* Shelby Bob Deso
* Royce Les Eayrs
* Chi Derek Elick
* Ali Keven Elian
* Royce Wes Eayrs
* Al Steven Ehsan
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* L Royce Cachola
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Arlie Gene Clan
* Arlie Rene Clan
* Cleo Asa Kazeck
* Dean Rory Roady
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elmo Rory Romey
* Ed Luigi Rigler
* Ed Luigi Ridler
* Doug Rory Rhudy
* Dino Rory Rondy
* Dong Rory Rondy
* Truman Asa Ruts
* Dana Rory Randy
* Dane Rory Randy
* Dino Rory Randy
* Dong Rory Randy
* Benito Ty Tunby
* Noel Asa Talent
* E Otha Vanasten
* Elijah Asa Wies
* N Mike Wedekind
* Ali Gene Setias
* Ali Jere Setias
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Louie Pete Sult
* Leo Dana Tabolt
* Leon Asa Tabolt
* Ed Luigi Sirles
* Al Teodoro Star
* Shelby Bob Leso
* Elijah Asa Lies
* Robt Lyle Libre
* Arlie Keven Lav
* Gino Lyle Lynge
* C Mike Mehelich
* Daryl Eli Lordi
* Gino Lyle Longe
* Daryl Ali Lordi
* Gary Lyle Lorge
* Cletus U Kubeck
* Duane Pete Ladt
* Robt Lyle Labre
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Kurt Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Shane Pete Last
* Dino Lyle Lande
* Dana Lyle Lande
* Dirk Lyle Larde
* Dong Lyle Lande
* Santo Coy Ounsy
* Morgan Asa Orms
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raimer
* Elijah Asa Pies
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Odis Asa Nacion
* Otis Asa Nacion
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* Elroy Ty Nygren
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5676 "PBFred"] ==
* Evil Anal Aziel
== From doranchak [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=30#p22403 (1)] [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=40#p22438 (2)]==
* A McNamara Scar
* Ate severed ear
* Trove Behemoth
* Spiro Motorist
* Laura Catapult
* Alice Venetian
* Agile Venetian
* Lebanon Enable
* Indiana Saudis
* Extras Adopted
* Athlete Lethal
* Achieve Lethal
* a Fine Venetian
* of Flanagan Fog
* to One Behemoth
* Extras Adapted
* Training Neat
* Chinese Eel Ice
* Artists Use Tau
* Our Bananas Ron
* Its Revered Sir
* Our Faraway Row
* Old Bikinis Don
* Of These Men Tom (or Of The Semen Tom)
* Greats To The Go
* Or I Was A Nation
* O He Was A Face Of
* [http://www.zodiackillerciphers.com/?p=152 Over 2,700 phrases from Project Gutenberg experiment]
* [https://docs.google.com/spreadsheets/d/13R16xILq6XIWTklErwZq7ltod7EG08-zeiG0AnAtsl4/edit?usp=sharing Another Project Gutenberg experiment, scanned 61.5 GB of text]
* [http://www.zodiackillerciphers.com/?p=467 From article], person names:
** Chastity Tracy
** Erica Natalie T
** Islami M Amelia
** Eddie Resendes
** Ernie Zerenner
** Aileen Enerlan
** Chitumu Eunice
** Ariyana Mariam
** Sripada Harish
** Ali Raja Mariam
** Arriaga Laura L
** Duitama David D
** Steve Menezes N
** Arriaza Laura L
** Arizala Maria M
** Adriana Laura L
** Aziz a Zahaniah
* [http://www.zodiackillerciphers.com/?p=467 From article], phrases / word combinations:
** Sarah The Horse
** Uncle Peter Cut
** Achieve Lethal
** Obscene Nelson
** Extreme Reuter
** Emperors Ropes
** Leigh The Haile
** Kane Pops Punks
** Gareth Tot Ergo
** Niece Gene Penn
** Drop Rarer Code
** Door Non-Encode
** Iraq Alan Again
** All Banana Alan
** Alice Venetian
** Laura Catapult
** Afghan Amalgam
** Reassess Scars
** Clara Cataract
** Shannon Encase
** Okinawa Nation
** Indiana Saudis
** Regan Adalard
** Drippy Peptide
** Outlet Erector
** Akira Canadian
** Adriana Marram
** Mary Nina Norma
** Robert Rory Bro
** Smile Pete List
** Mary Tate Terme
** Mary Gags Germs
** Ryan Amaya Gary
** Daniel Eye Andy
** Eats Bobs Bates
** Kill Baby Bulky
** Shit Pipe Poise
** Eric Alan Alien
** Slave Pete Last
** Extra War After
** Murder Eye Army
** Clara Fatal Act
** Encoded Odd CEO
** [http://zodiackillerciphers.com/z13wordsearch-results-2-sorted.txt List of 283 phrases / word combinations that use two words]
** [http://zodiackillerciphers.com/z13wordsearch-results-3-sorted.txt List of 1,283,443 phrases / word combinations that use three words]
* From another corpus test for [https://www.reddit.com/r/ZodiacKiller/comments/axqx4z/z13_my_name_is_cipher/ reddit post]:
** Chief of Africa
** Uncle Peter Cut
** of Hair It Is Hot
** of These Newton
** at Me O Son of Man
** a Wide Venetian
** a Ripe Venetian
** Avis, a Canadian
** India. Was, and Is.
** I Saw Alan Again
** I Was a Man Again
** I Had a Man Again
** Near a Way As Any
** Claus Asks Jack
** Guest at Otsego
** One Has a Name on
** One Had an Axe on
** As if a Canadian
** Oh No It It Is Not
** Is That As Art Is
** Nearer Eden and
** Niagara Day And
** [http://zodiackillerciphers.com/z13-corpus-solutions.txt Full unprocessed results]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4305&p=69616 More results from corpus scanning:]
** So I'm a Satanist
** So I'm a Fatalist (from glurk)
** A Dog, a Cat, a Goat
** or Steve Nelson
** As I Had an Asian
** a Kid: a Canadian
** Emperor's Ropes
** As Real As Auras
** That I Die, I Hate
** One Has a Name on
** I've Had an Axe in
** Spectate These
** if I Was a Nazi in
** I Eat a Banana in
** As I'm a Canadian
** I Was a Canadian
** Leave Helen All
** Edit As an Alien
** Shakalaka Mask
** Shit! a Natalist!
** Shit! a Fatalist!
** Shit! a Satanist!
** Is a Pagan Again
** Extra Caracter
** and Gamal Abdal
** Donut. It Stands.
** Al Is a Canadian
** Reign on Entire
** I've Had a Dane I.D.
** Least It Steals
** Ratio, Do You Try?
** Said As a Taoist

== From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6406 "Deryk"] ==
* Male, Initial: M.T.
== From [https://www.tapatalk.com/groups/zodiackillerfr/my-name-is-zodiac-t2276-s20.html#p139086 "MickCal"] ==
* OL STEVE NELSON
== From [https://discord.com/channels/996952324150931477/996952376894292018/1135335122527342604 "Toad"] ==
* AMIGO COLONIAL
== From [https://discord.com/channels/996952324150931477/996952376894292018/1033254655381217320 "Antisquid42"] ==
* John E. Heresh Jr.
* Donald LeLinde
* Neal O’Donovann
* Doug Lyle Laude
* Chip O. Kozowicz
* Seth Everett Sr.
* Andrew E. Levdal
* Paul Lyle Loupe
* Shiloh Oto List
* Juan O. Corona Jr.
* Frank X. LeLoafe
* Leo Solomon Olm
== From [https://zodiackillerciphers.com/z13_2_word_solutions.txt "rando"] ==
* [https://zodiackillerciphers.com/z13_2_word_solutions.txt 3,142 2-word solutions]

== Partial solution from [http://zodiackiller.21.forumer.com/viewtopic.php?p=119889#119889 "granny101"] ==
* ILLNEVETELLIT ("I'LL NEVER TELL IT", with the "R" missing)

= Solutions that fit if you first reverse the cipher =

TODO

= Solutions that fit the ciphertext if you permit anagramming =

Rearranging the cipher text significantly reduces the constraints on possible solutions. As [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=20#p13716 "glurk"] points out, anagramming the 13 symbols permits a very large variety of possible solutions, which makes it nearly impossible to validate any given solution derived this way.

Here are some examples of solutions that arise from anagramming:

* [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=40#p13807 Small sampling from "sincos"]
* From doranchak:
** 13-letter English words that have the same letter distribution as the symbols of the cipher:
*** international, participation, concentration, interventions, investigating, participating, inappropriate, investigative, authoritarian, mediterranean, intentionally, accommodation, strengthening, commissioners, differentiate, collaborators, incorporation, unwillingness, mismanagement, superstitious, mathematician, nationalities, instantaneous, nationalistic, inconsistency, choreographer, preponderance, condescending, applicability, contingencies, indeterminate, sarcastically, temperamental, disillusioned, prerequisites, intelligences, irreplaceable, headquartered, reincarnation, proportionate, appropriating, inclusiveness, preservatives, ornamentation, uninteresting, incapacitated, contaminating, irrationality, abolitionists, improprieties, structuralist, sharecroppers, solicitations, intermarriage, arbitrariness, impermissible, disconnection, professorship, scintillating, insufficiency, spectroscopic, satisfactions
** Small sampling of 13-letter surnames that have the same letter distribution as the symbols of the cipher:
*** radhakrishnan, bhattacharjee, villavicencio, chattopadhyay, oluwatobiloba, degraffenreid, knappenberger, brandenburger, hebblethwaite, rathakrishnan, degraffenried, sahasrabuddhe, stamatopoulos, schlegelmilch, sastrowardoyo, konstantinova, muruganantham, thorsteinsson, madhusoodanan, wojciechowicz, hintermeister, klingenberger, vansteenkiste, raveendranath, blankenbiller, messerschmitt, abdollahzadeh, vlaisavljevic, stamatopoulou, giacomantonio, gebregziabher, gardarsdottir, blattenberger, agustiningsih, sverrisdottir, shirmohammadi, reichenbacher, schottenstein, christophoros, javakhishvili, sundareswaran, schiermeister, kaluhiokalani, natsvlishvili, monteferrante, ntakirutimana, derakhshandeh, winternheimer, spangenberger, liechtenstein, heiderscheidt, chandrarathne, shettlesworth
** [http://zodiackillerciphers.com/all-names-z13-list2-sorted.txt A sampling of 69,607 common first-last name combinations] that have the same letter distribution as the symbols of the cipher.
*** [http://zodiackillersite.com/viewtopic.php?p=18552#p18552 (Original broken forum link)]
* From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6376 Tom Voigt]:
** knickerbocker
** [http://zodiackiller.21.forumer.com/viewtopic.php?p=120299#120299 aintgonnatell]
* From [http://www.santarosahitchhikermurders.com/ Deb Silva]:
** [http://en.wikipedia.org/wiki/Bobby_Beausoleil Bob Beausoleil]
* From Anonymous:
** Jimmy Phillips (also credited to [http://zodiackiller.fr.yuku.com/topic/3827/Jimmy-Phillips alanbenjy])
* From Christer Böke:
** Frank Frazetta ([http://zodiackillersite.com/viewtopic.php?f=63&t=1275 Tim Holt] was drawn by Frank Bollle and Frank Frazetta)
** Grant Santiago
* From [https://www.tapatalk.com/groups/zodiackillerfr/simple-solve-for-the-my-name-is-t8738.html#p145360 jaydeezodiachunter]:
** Debbie Faraday

= Solutions that fit if you relax other constraints of the cipher =

Solutions that fit if you allow all three "circled 8" symbols to be wildcards:
* From Michael Kelleher:
** thebigsecrete
Solutions that are produced via multiple operations:
* From [http://www.zodiackillerciphers.com/?p=46 Lyndon Lafferty]:
** NAME GRANT, or NAME IS GRANT
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/detailed-solution-to-z13-and-z32/ Faycal Ziraoui's solution]
A solution that applies the 408 key and interprets some symbols as nulls:
* from [http://zodiackiller.fr.yuku.com/topic/6839/Zodiacs-Name-using-408-Key Rembrandt]:
** ED SHAW
Solutions with one name part in the middle, and another name part split in half and written backwards:
* [http://www.zodiackillersite.com/viewtopic.php?p=69126#p69126 DEBBIE FARADAY]

= Other interpretations =

* "My name is" contains 8 letters. The cipher text contains 8 letters and 5 special symbols. The special symbols contain Zodiac's name and the rest just mean "My name is" (Source: Jeppesen)
* [https://www.tapatalk.com/groups/zodiackillerfr/general-book-discussion-for-hunted-the-zodiac-murd-t10141.html#p197345 "Set addition" interpretation of Z13 by Doug Oswell], resulting in solution: "FROM TED KACZYNS[K]I"
* [https://www.tapatalk.com/groups/zodiackillerfr/paul-astrup-s-theory-meteorological-symbols-challe-t10261.html#p202558 Weather symbols]
* The line after "My name is" is roughly above symbols that resemble "Tom" spelled backwards. (Source: David Cauley via YouTube comments)

Z13 Solutions

2024-01-03T16:57:38Z

Admin: /* From "Antisquid42" */

= Solutions that fit the ciphertext as is =

This section only shows proposed solutions that fit the cipher text "as is". No anagramming or other re-arrangements are used here, and the cipher is considered to be strictly a substitution cipher. Solutions that permit anagramming are very easy to come by, as there are several billion possible string combinations to choose from. Solutions that do not require anagramming are still numerous, however, which increases the difficulty of knowing which one is correct.

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=50&t=1390&p=24191#p24190 "Quill"] ==
* Eddie Penerden
* Stan T E Case (using "8"s as spaces)
* Greg N A Vega (using "8"s as spaces)

== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5677 "glurk"] (homophonic solutions) ==
* Steve Pete West
* Adrian a Harrah
* Shannon E Nease
* Steve Pete Best
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Eddie Gene Oden
* Steve Pete Vest
* Barney E Yearby
* Gene Lyle Lange
* Eddie Gene Eden
* Ed Steven Eisen
* E Alva Vanallen
* Angelo Lyle Gay
* Eddie Rene Oden
* Isreal a Sarris
* Carl Bob Abarca
* Elliot O Roller
* Andre Reyes Day
* Ed Steve Nelsen
* Shane Pete East
* Lee Gene Levell
* Eddie Rene Eden
* Rueben E Segers
* Rueben E Severs
* Eddie Gene Aden
* Eddie Dewey Dew
* Shane Pete Mast
* Ed Steve Reeser
* Ed Steve Reiser
* Lee Rene Levell
* Neal Alan Amann
* Sean Lyle Lease
* Otto Alan Alton
* Otto Alan Acton
* Otto Alan Aston
* Otto Alan Anton
* Eddie Rene Aden
* Lee Jamal Abell
* Andre Gene Adan
* Reed Alan Ahern
* Shane Pete Fast
* Elliot O Yokley
* Elliot O Soules
* Lee Pete Levell
* Ira Lamar Adair
* Neil Lyle Laine
* Teodoro Tom Ott
* Otto Adam Altom
* Noah Alan Amann
* Eddy Alan Alden
* Lee Jewel Ezell
* Cory Bob Abarca
* Andre Rene Adan
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Earle Gene Wren
* Dean Rory Ready
* Dana Bob Obando
* Luis Rory Reily
* Otto Asa Santos
* Eric Asa Rapier
* Gino Lyle Lange
* Eddy Alan Arden
* Kent Lyle Linke
* Andre Dewey Daw
* Eddie Les Eades
* Louie Pete Ault
* Eddie Jewel Dew
* Ian Reyes Ennis
* Edison O Rosier
* Ollie Lee Enloe
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Ira Jamar Adair
* Earle Rene Wren
* Ernie Dewey New
* Lee Jewel Ewell
* Eddie Wes Eades
* Drew Rory Reedy
* Al Isaias Arias
* Ollie Derek Lor
* Cary Bob Abarca
* Emile Gene Lien
* Arlie Dewey Law
* Ollie Dewey Low
* Rob Dewey Embry
* Curt Bob Abarca
* Earl Asa Laurel
* Stefan Asa Hess
* Eddie Reyes Dey
* Eli Dana Rapier
* Dane Bob Obando
* Elmo Rory Ramey
* Lee Jere Levell
* Ali Rufus Urias
* Emile Rene Lien
* Eddie Jere Eder
* Stan Lyle Lease
* Chi Derek Edick
* Earle Gene Oren
* Emile Gene Bien
* Earle Gene Uren
* Arturo Rory Tao
* Otis Asa Nation
* Genaro Rory Ngo
* Dane Lyle Linde
* Dane Lyle Lynde
* Dane Lyle Lunde
* Scot Lyle Loose
* Ali Reyes Elias
* Art Solomon Tam
* Donn Bob Obando
* Dino Bob Obando
* Andre Jewel Daw
* Neal Adan Amann
* Emile Rene Bien
* Otto Adan Alton
* Earle Rene Uren
* Otto Adan Acton
* Earle Rene Oren
* Otto Adan Anton
* Otto Adan Aston
* Dallas Asa Olds
* Erik Asa Rapier
* Reed Adan Ahern
* Ernie Jewel New
* Donn Lyle Linde
* Dino Lyle Linde
* Donn Lyle Lynde
* Dino Lyle Lunde
* Donn Lyle Lunde
* Dino Lyle Lynde
* Dong Bob Obando
* Teodoro Tod Ott
* Stefan Asa Bess
* Noah Adan Amann
* Arlie Jewel Law
* Issac Jc Ocasio
* Arlie Reyes Lay
* Ed Teodoro Ater
* Ollie Jewel Low
* Eddy Adan Alden
* Shad Lyle Lease
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Shon Lyle Loose
* Dong Lyle Lunde
* Ollie Reyes Loy
* Stefan Asa Ness
* Earle Dewey Rew
* Reed Asa Sayers
* Anibal Asa Dias
* Noe Reyes Edens
* Delmar Asa Olds
* Isreal Al Abril
* Isreal Al April
* Earle Reyes Rey
* Ernie Les Eanes
* Eddy Adan Arden
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Ernie Reyes Ney
* Morgan Asa Arms
* Olin Asa Nation
* Lou Solomon Ulm
* Ernie Wes Eanes
* Ernie Rey Edney
* Odis Asa Nation
* Murray Asa Arms
* Noe Reyes Evens
* Ollie Dee Enloe
* Leif Rory Reily
* Elmo Asa Raymer
* Isaiah Asa Sais
* Anibal Asa Bias
* Ollie Jere Flor
* Reed Asa Sagers
* Reed Asa Sauers
* Stefan Asa Vess
* Stefan Asa Jess
* Stefan Asa Gess
* Ezra Asa Laurel
* Erin Asa Rapier
* Emile Jere Mier
* Emile Jere Pier
* Emile Jere Bier
* Earle Jewel Rew
* Emile Jere Wier
* Emile Jere Kier
* Anibal Asa Sias
* Isaias Asa Sais
* Paris Asa Serpa
* Arlie Jere Klar
* Luigi Gil Ifill
* Hai Solomon Ihm
* Darell L Ilardi
* Chi Derek Emick
* Eddie Lee Emdee
* Daryl Al Ilardi
* Arlie Rey Emlay
* Eddie Rene Iden
* Chi Derek Enick
* Earle Rene Hren
* Trevor O Howeth
* Earle Gene Hren
* Duncan Asa Ends
* Danial Asa Ends
* Louie Pete Hult
* Eddie Gene Iden
* Chas Asa Kasack
* Clay Asa Kasack
* Lee Jewel Euell
* Chad Asa Kasack
* Ian Dana Katnik
* Chet Asa Kazeck
* Shane Pete Kast
* Leo Jewel Etoll
* Ian Dana Kamnik
* M Keenan Ingemi
* M Vernon Ingemi
* Ernie Jere Iner
* Eddie Dee Emdee
* Isaias Asa Kais
* Ed Steven Elsen
* Steve Pete Jest
* Isaiah Asa Kais
* Theron O Howeth
* Neil Asa Garing
* Ernie Wes Ennes
* Noah Asa Galang
* Shane Leo Eraso
* Steve Pete Gest
* Emile Jere Gier
* Israel E Gehrig
* N Eugene Genung
* Neal Asa Galang
* Elijah Asa Fies
* Steve Pete Fest
* Eli Peter Etier
* Ed Steven Essen
* Stefan Asa Fess
* Chi Derek Erick
* Ollie Pete Flot
* Earle Pete Fret
* Ernie Ben Ennen
* Emile Jere Hier
* Ernie Len Ennen
* Ernie Ken Ennen
* Theron O Horeth
* Trevor O Horeth
* Lee Bo Holowell
* Chi Derek Evick
* Ernie Les Ennes
* Adrian Asa Gras
* Earle Gene Gren
* Noe Reyes Ewens
* Ollie Jere Glor
* Shad Asa Habash
* Stan Asa Habash
* Earle Rene Gren
* Sean Asa Habash
* Aldo Alan Ardan
* Andy Adan Ardan
* Art Jamal Antal
* Aldo Adan Ardan
* Eli Jamal Ariel
* Elijah Al Ariel
* Andy Alan Ardan
* Dorian Asa Ards
* Leland N Analla
* R Keenan Andera
* Lee Jamal Amell
* Ty Isaiah Amith
* L Vernon Angela
* Antwan Al Antal
* R Vernon Andera
* L Keenan Angela
* Ed Isaias Aries
* Art Jamal Attal
* Elmo Adan Aumen
* Shane Peter Ast
* Antwan Al Attal
* Otto Alan Auton
* Isreal Al Avril
* Elmo Alan Aumen
* Otto Adan Auton
* Elmo Alan Armen
* Norman Asa Arns
* Isreal Asa Aris
* Elmo Adan Armen
* Alva Adan Arvan
* Alva Alan Arvan
* Otto Adan Arton
* Otto Alan Arton
* Otto Adan Afton
* Otto Alan Afton
* Eddie Jere Ader
* Duane Reyes Ady
* Isaias Adam Aid
* Isaias Adan Aid
* Isaiah Adam Aid
* Isaiah Adan Aid
* Lyle Bob Abella
* Blake Peter Abt
* Ira Jamar Abair
* Ira Lamar Abair
* Chase Reyes Acy
* Lee Jamal Adell
* Tobias Asa Abts
* Derick C Acorda
* Otto Adan Aiton
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Aron Adan Aloan
* Aron Alan Aloan
* Amos Adan Aloan
* Amos Alan Aloan
* Arlie Gene Alan
* Arlie Rene Alan
* Otto Alan Aiton
* Nigel Al Alagna
* Cecil Al Alecca
* Al Isaias Alias
* Arlie Jere Alar
* Bradly L Aldaba
* Arlie Jewell Aw
* Emile Jere Dier
* Elijah Asa Dies
* Emile Gene Dien
* Emile Rene Dien
* Rey Reyes Eayrs
* Roy Reyes Eayrs
* Les Dewey Easly
* Ray Reyes Eayrs
* Earl E Deserres
* Eddie Derek Der
* Earle Deserres
* Stefan Asa Dess
* Steve Pete Dest
* Ezra E Deserres
* Shelby Bob Deso
* Royce Les Eayrs
* Eddie Ben Elden
* Eddie Ken Elden
* Eddie Ken Eiden
* Eddie Len Eiden
* Chi Derek Elick
* Lee Solomon Elm
* Eddie Len Elden
* Ali Keven Elian
* Lee Jewel Edell
* Arlie Leo Edlao
* Royce Wes Eayrs
* Ed Steven Ebsen
* Al Steven Ehsan
* Eddie Ben Eiden
* Reuben Ed Efurd
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* Earle Rene Bren
* Robert Rory Bro
* L Rocco Cachola
* L Royce Cachola
* Royce Rene Byrn
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Otto Adan Axton
* Otto Alan Axton
* Adrian Asa Bras
* Earle Gene Bren
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Leo Gene Debold
* Leo Jere Debold
* Isaias Asa Dais
* Andre Derek Dar
* Leonel E Debold
* Lionel E Debold
* Leo Pete Debold
* Leo Rene Debold
* N Royce Cicconi
* Arlie Gene Clan
* N Boyce Cicconi
* N Rocco Cicconi
* Bruce Jere Cubr
* Isaiah Asa Dais
* Arlie Rene Clan
* Arlie Jere Clar
* Cleo Asa Kazeck
* Dean Rory Roady
* Ryan Rory Roary
* Ed Luigi Riller
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elwood O Rohwer
* Elmo Rory Romey
* Ed Luigi Rigler
* Deon Rory Rhody
* Dion Rory Rhody
* Eli Rene Revier
* Eliseo E Revier
* Ed Luigi Ridler
* Drew Rory Riedy
* Doug Rory Rhudy
* Anibal Asa Rias
* Dino Rory Rondy
* Ivan Asa Salais
* Silas Asa Salsa
* Isaiah a Salais
* Isaias a Salais
* Thomas a Sanots
* Troy Asa Sanots
* Alva Asa Salvas
* Denis Asa Sanda
* Ira Dana Salais
* Cesar Ira Rosca
* Drew Rory Ruedy
* Dong Rory Rondy
* Donn Rory Rondy
* Neil Asa Sabins
* Eloy Asa Sagoes
* Truman Asa Ruts
* Emery Ty Ryneer
* Eli Gene Regier
* Eli Jere Regier
* Ryan Rory Reary
* Ed Steve Reaser
* Eliseo E Regier
* Elmo Rory Remey
* Eli Pete Regier
* Eli Rene Regier
* Ezra Rory Rarey
* Dana Rory Randy
* Dane Rory Randy
* Art Dana Rajtar
* Elmo Asa Rammer
* Donn Rory Randy
* Earl Rory Rarey
* Dino Rory Randy
* Dong Rory Randy
* Eli Gene Renier
* Eddy E Resendes
* Stefan Asa Ress
* Ed Dee Resendes
* Eli Jere Revier
* Eli Pete Revier
* Alva Rory Revay
* Eli Gene Revier
* Eddie Resendes
* Eli Rene Renier
* Eliseo E Renier
* Eli Jere Renier
* Eli Pete Renier
* Art Pete Rentar
* Art Rene Rentar
* Art Gene Rentar
* Art Jere Rentar
* Alva Asa Sarvas
* Emmitt Ty Tomey
* Emmett Ty Tumey
* Emile Pete Tiet
* Emmett Ty Tomey
* Isaiah Asa Vais
* Isaias Asa Vais
* Emmitt Ty Tumey
* Benito Ty Tunby
* Emile Jere Tier
* T Dusty Tatsuta
* T Rusty Tatsuta
* Noe Dana Talent
* Noel Asa Talent
* Emile Gene Tien
* Emile Rene Tien
* Stefan Asa Tess
* Steve Pete Test
* E Otha Vanasten
* Elijah Asa Wies
* Isaiah Asa Zais
* Emile Gene Wien
* Emile Rene Wien
* Emile Rene Zien
* Emile Jere Zier
* Isaias Asa Zais
* Emile Gene Zien
* Stefan Asa Wess
* Emile Rene Vien
* Emile Jere Vier
* Anibal Asa Vias
* Emile Gene Vien
* N Mike Wedekind
* Neil E Wedekind
* Isaiah Asa Wais
* Isaias Asa Wais
* Ali Gene Setias
* Ali Jere Setias
* Noe Rene Serens
* Moses Asa Sesma
* Louis Asa Shula
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Noe Pete Serens
* Ezra Asa Sayres
* Rueben E Sebers
* Reed Asa Savers
* Earl Asa Sayres
* Noe Gene Serens
* Noe Jere Serens
* Miles Asa Selma
* Myles Asa Selma
* Emile Gene Sien
* Thad Asa Tabatt
* Tuan Asa Tabatt
* Ed Teodoro Ster
* Louie Pete Sult
* Duane Pete Tadt
* Graham Asa Tags
* Leo Dana Tabolt
* Leon Asa Tabolt
* Antwan Asa Stas
* Al Luigi Sillas
* Ed Luigi Sirles
* Emile Rene Sien
* Emile Jere Sier
* Louis Asa Soula
* Al Teodoro Star
* Ollie Pete Slot
* Edison O Solies
* Shelby Bob Leso
* Stefan Asa Less
* Tony Lyle Lente
* Zane Lyle Lenze
* Bret Lyle Liebe
* Elijah Asa Lies
* Anibal Asa Lias
* Robt Lyle Libre
* King Lyle Lenke
* Lee Dana Layell
* Eddy Lyle Ledee
* Arlie Keven Lav
* Lee Dana Lavell
* Lyle Lyle Lelle
* Kent Lyle Lenke
* Theo Lyle Leete
* Trey Lyle Leete
* Gene Lyle Longe
* Gino Lyle Lynge
* Isaiah Asa Mais
* Cecil Eli Lucci
* Gene Lyle Lynge
* I Otha Masaitis
* C Mike Mehelich
* Isaias Asa Mais
* Eddy a Marander
* Cecil Ali Lucci
* Daryl Eli Lordi
* Earl Lyle Loree
* Gino Lyle Longe
* Daryl Ali Lordi
* Ollie Peter Lot
* Paul Lyle Loupe
* Ezra Lyle Loree
* Gary Lyle Lorge
* Alvaro R Krivak
* Cletus U Kubeck
* W Rocky Knknown
* Adrian Asa Kras
* Duane Pete Ladt
* Isaiah Asa Lais
* Robt Lyle Labre
* Lee Dana Ladell
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Keenan Asa Keks
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Stefan Asa Kess
* Isaias Asa Lais
* Kurt Lyle Larke
* Vern Lyle Larve
* Kirk Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Lee Dana Lasell
* Shane Pete Last
* Karl Lyle Larke
* Dane Lyle Lande
* Dino Lyle Lande
* Elmo Asa Lammel
* Dana Lyle Lande
* Zane Lyle Lanze
* Dirk Lyle Larde
* Dong Lyle Lande
* Donn Lyle Lande
* Stefan Asa Mess
* Genaro R Orengo
* Isreal Asa Oris
* Otto Everett or
* Adrian Asa Oras
* Al Teodoro Otar
* Santo Coy Ounsy
* Morgan Asa Orms
* Murray Asa Orms
* Teodoro O Omoto
* Steve Pete Oest
* Emile Gene Oien
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Leo Solomon Olm
* Emile Rene Oien
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raemer
* Eddy Asa Raider
* Eddy Asa Radder
* Eddy Asa Raeder
* Isaias Asa Rais
* Antwan a Rajtar
* Elmo Asa Raimer
* Isaiah Asa Rais
* Adrian Adan Rad
* Isaias Asa Pais
* Elijah Asa Pies
* Ollie Jewell Ow
* Isaiah Asa Pais
* Rupert Rory Pro
* Adrian Adam Rad
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Isaias a Narain
* Ivan Asa Narain
* Steve Pete Nest
* Ernie Peter Net
* Ed Steve Neisen
* Ed Steve Nessen
* Isaiah a Narain
* Shannon Z Naasz
* Odis Asa Nacion
* Anibal Asa Mias
* Al Luigi Millam
* Otto Asa Nanton
* Ira Dana Narain
* Olin Asa Nacion
* Otis Asa Nacion
* Ernie Keven Nev
* L Damon Odonald
* L Daron Odonald
* L Aaron Odonald
* L Carol Odonald
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* L Jarod Odonald
* Eddie Jere Oder
* Austin I Nissan
* Elliot O Nowlen
* Emile Jere Nier
* Ian Solomon Nim
* Neal Bob Obiano
* Noah Bob Obiano
* Elroy Ty Nygren
* Emery Ty Nyreen
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5733 "glurk"] (non-homophonic solutions) ==
* Gary Lyle Large
* Israel E Negrin
* Ashley E Mecham
* Elijah a Rapier
* Angelo Lyle Gay
* Andre Reyes Day
* Shane Pete Mast
* Shane Pete Fast
* Edison O Rozier
* Shane Pete Gast
* Shane Pete Rast
* Shane Pete Bast
* Arnold Lyle Nay
* Dean Rory Ready
* Luis Rory Reily
* Gino Lyle Lange
* Louie Pete Ault
* Edison O Rosier
* Dana Lyle Linde
* Dana Lyle Lynde
* Dana Lyle Lunde
* Arlie Dewey Law
* Rob Dewey Embry
* Eli Dana Rapier
* Elmo Rory Ramey
* Ali Rufus Urias
* Chi Derek Edick
* Otis Asa Nation
* Ali Reyes Elias
* Art Solomon Tam
* Andre Jewel Daw
* Dino Lyle Linde
* Dino Lyle Lunde
* Dino Lyle Lynde
* Arlie Reyes Lay
* Rudolf Lyle Dry
* King Lyle Linke
* Dong Lyle Lynde
* Dong Lyle Linde
* Elijah Asa Ries
* Dong Lyle Lunde
* Delmar Asa Olds
* Elijah Asa Nies
* Emil Asa Rapier
* Elijah Asa Gies
* Odis Asa Nation
* Leif Rory Reily
* Elmo Asa Raymer
* Hai Solomon Ihm
* Chi Derek Emick
* Daryl Al Ilardi
* Arlie Rey Emlay
* Chi Derek Enick
* Trevor O Howeth
* Louie Pete Hult
* Chet Asa Kazeck
* Shane Pete Kast
* M Vernon Ingemi
* Neil Asa Garing
* Shane Leo Eraso
* Israel E Gehrig
* Elijah Asa Fies
* Chi Derek Erick
* Trevor O Horeth
* Chi Derek Evick
* L Vernon Angela
* Elmo Adan Aumen
* Shane Peter Ast
* Elmo Alan Aumen
* Elmo Alan Armen
* Elmo Adan Armen
* Duane Reyes Ady
* Blake Peter Abt
* Chase Reyes Acy
* Derick C Acorda
* Elmo Adan Almen
* Elmo Alan Almen
* Eli Jamar Alier
* Eli Lamar Alier
* Elijah Asa Dies
* Shelby Bob Deso
* Royce Les Eayrs
* Chi Derek Elick
* Ali Keven Elian
* Royce Wes Eayrs
* Al Steven Ehsan
* Ian Reyes Ehnis
* Louie Pete Bult
* Royce Gene Byrn
* L Royce Cachola
* L Boyce Cachola
* Doyle Pete Aydt
* Elijah Asa Bies
* Arlie Gene Blan
* Arlie Rene Blan
* Shane Pete Cast
* Arlie Gene Clan
* Arlie Rene Clan
* Cleo Asa Kazeck
* Dean Rory Roady
* Ed Luigi Risler
* Dana Rory Rondy
* Dane Rory Rondy
* Elmo Rory Romey
* Ed Luigi Rigler
* Ed Luigi Ridler
* Doug Rory Rhudy
* Dino Rory Rondy
* Dong Rory Rondy
* Truman Asa Ruts
* Dana Rory Randy
* Dane Rory Randy
* Dino Rory Randy
* Dong Rory Randy
* Benito Ty Tunby
* Noel Asa Talent
* E Otha Vanasten
* Elijah Asa Wies
* N Mike Wedekind
* Ali Gene Setias
* Ali Jere Setias
* Ed Luigi Sidles
* Ali Pete Setias
* Ali Rene Setias
* Louie Pete Sult
* Leo Dana Tabolt
* Leon Asa Tabolt
* Ed Luigi Sirles
* Al Teodoro Star
* Shelby Bob Leso
* Elijah Asa Lies
* Robt Lyle Libre
* Arlie Keven Lav
* Gino Lyle Lynge
* C Mike Mehelich
* Daryl Eli Lordi
* Gino Lyle Longe
* Daryl Ali Lordi
* Gary Lyle Lorge
* Cletus U Kubeck
* Duane Pete Ladt
* Robt Lyle Labre
* Arlie Rene Klan
* Chi Jere Kemick
* Chi Pete Kemick
* Chi Gene Kemick
* Elijah Asa Kies
* Arlie Gene Klan
* Chi Rene Kemick
* Kurt Lyle Larke
* Kory Lyle Larke
* Arlie Peter Lat
* Doug Lyle Laude
* Shane Pete Last
* Dino Lyle Lande
* Dana Lyle Lande
* Dirk Lyle Larde
* Dong Lyle Lande
* Santo Coy Ounsy
* Morgan Asa Orms
* L Mason Odonald
* L Ramon Odonald
* Arlie Rene Olan
* Arlie Gene Olan
* Santo Roy Ounsy
* Elmo Asa Raimer
* Elijah Asa Pies
* Arlie Gene Plan
* Arlie Rene Plan
* Shane Jere Nasr
* Shane Pete Nast
* Odis Asa Nacion
* Otis Asa Nacion
* L Jason Odonald
* L Major Odonald
* L Jacob Odonald
* Elroy Ty Nygren
== From [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=375#p5676 "PBFred"] ==
* Evil Anal Aziel
== From doranchak [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=30#p22403 (1)] [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=52&t=1305&start=40#p22438 (2)]==
* A McNamara Scar
* Ate severed ear
* Trove Behemoth
* Spiro Motorist
* Laura Catapult
* Alice Venetian
* Agile Venetian
* Lebanon Enable
* Indiana Saudis
* Extras Adopted
* Athlete Lethal
* Achieve Lethal
* a Fine Venetian
* of Flanagan Fog
* to One Behemoth
* Extras Adapted
* Training Neat
* Chinese Eel Ice
* Artists Use Tau
* Our Bananas Ron
* Its Revered Sir
* Our Faraway Row
* Old Bikinis Don
* Of These Men Tom (or Of The Semen Tom)
* Greats To The Go
* Or I Was A Nation
* O He Was A Face Of
* [http://www.zodiackillerciphers.com/?p=152 Over 2,700 phrases from Project Gutenberg experiment]
* [https://docs.google.com/spreadsheets/d/13R16xILq6XIWTklErwZq7ltod7EG08-zeiG0AnAtsl4/edit?usp=sharing Another Project Gutenberg experiment, scanned 61.5 GB of text]
* [http://www.zodiackillerciphers.com/?p=467 From article], person names:
** Chastity Tracy
** Erica Natalie T
** Islami M Amelia
** Eddie Resendes
** Ernie Zerenner
** Aileen Enerlan
** Chitumu Eunice
** Ariyana Mariam
** Sripada Harish
** Ali Raja Mariam
** Arriaga Laura L
** Duitama David D
** Steve Menezes N
** Arriaza Laura L
** Arizala Maria M
** Adriana Laura L
** Aziz a Zahaniah
* [http://www.zodiackillerciphers.com/?p=467 From article], phrases / word combinations:
** Sarah The Horse
** Uncle Peter Cut
** Achieve Lethal
** Obscene Nelson
** Extreme Reuter
** Emperors Ropes
** Leigh The Haile
** Kane Pops Punks
** Gareth Tot Ergo
** Niece Gene Penn
** Drop Rarer Code
** Door Non-Encode
** Iraq Alan Again
** All Banana Alan
** Alice Venetian
** Laura Catapult
** Afghan Amalgam
** Reassess Scars
** Clara Cataract
** Shannon Encase
** Okinawa Nation
** Indiana Saudis
** Regan Adalard
** Drippy Peptide
** Outlet Erector
** Akira Canadian
** Adriana Marram
** Mary Nina Norma
** Robert Rory Bro
** Smile Pete List
** Mary Tate Terme
** Mary Gags Germs
** Ryan Amaya Gary
** Daniel Eye Andy
** Eats Bobs Bates
** Kill Baby Bulky
** Shit Pipe Poise
** Eric Alan Alien
** Slave Pete Last
** Extra War After
** Murder Eye Army
** Clara Fatal Act
** Encoded Odd CEO
** [http://zodiackillerciphers.com/z13wordsearch-results-2-sorted.txt List of 283 phrases / word combinations that use two words]
** [http://zodiackillerciphers.com/z13wordsearch-results-3-sorted.txt List of 1,283,443 phrases / word combinations that use three words]
* From another corpus test for [https://www.reddit.com/r/ZodiacKiller/comments/axqx4z/z13_my_name_is_cipher/ reddit post]:
** Chief of Africa
** Uncle Peter Cut
** of Hair It Is Hot
** of These Newton
** at Me O Son of Man
** a Wide Venetian
** a Ripe Venetian
** Avis, a Canadian
** India. Was, and Is.
** I Saw Alan Again
** I Was a Man Again
** I Had a Man Again
** Near a Way As Any
** Claus Asks Jack
** Guest at Otsego
** One Has a Name on
** One Had an Axe on
** As if a Canadian
** Oh No It It Is Not
** Is That As Art Is
** Nearer Eden and
** Niagara Day And
** [http://zodiackillerciphers.com/z13-corpus-solutions.txt Full unprocessed results]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4305&p=69616 More results from corpus scanning:]
** So I'm a Satanist
** So I'm a Fatalist (from glurk)
** A Dog, a Cat, a Goat
** or Steve Nelson
** As I Had an Asian
** a Kid: a Canadian
** Emperor's Ropes
** As Real As Auras
** That I Die, I Hate
** One Has a Name on
** I've Had an Axe in
** Spectate These
** if I Was a Nazi in
** I Eat a Banana in
** As I'm a Canadian
** I Was a Canadian
** Leave Helen All
** Edit As an Alien
** Shakalaka Mask
** Shit! a Natalist!
** Shit! a Fatalist!
** Shit! a Satanist!
** Is a Pagan Again
** Extra Caracter
** and Gamal Abdal
** Donut. It Stands.
** Al Is a Canadian
** Reign on Entire
** I've Had a Dane I.D.
** Least It Steals
** Ratio, Do You Try?
** Said As a Taoist

== From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6406 "Deryk"] ==
* Male, Initial: M.T.
== From [https://www.tapatalk.com/groups/zodiackillerfr/my-name-is-zodiac-t2276-s20.html#p139086 "MickCal"] ==
* OL STEVE NELSON
== From [https://discord.com/channels/996952324150931477/996952376894292018/1135335122527342604 "Toad"] ==
* AMIGO COLONIAL
== From [https://discord.com/channels/996952324150931477/996952376894292018/1033254655381217320 "Antisquid42"] ==
* John E. Heresh Jr.
* Donald LeLinde
* Neal O’Donovann
* Doug Lyle Laude
* Chip O. Kozowicz
* Seth Everett Sr.
* Andrew E. Levdal
* Paul Lyle Loupe
* Shiloh Oto List
* Juan O. Corona Jr.
* Frank X. LeLoafe
* Leo Solomon Olm
== From [https://zodiackillerciphers.com/z13_2_word_solutions.txt "rando"]
* [https://zodiackillerciphers.com/z13_2_word_solutions.txt 3,142 2-word solutions]

== Partial solution from [http://zodiackiller.21.forumer.com/viewtopic.php?p=119889#119889 "granny101"] ==
* ILLNEVETELLIT ("I'LL NEVER TELL IT", with the "R" missing)

= Solutions that fit if you first reverse the cipher =

TODO

= Solutions that fit the ciphertext if you permit anagramming =

Rearranging the cipher text significantly reduces the constraints on possible solutions. As [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=20#p13716 "glurk"] points out, anagramming the 13 symbols permits a very large variety of possible solutions, which makes it nearly impossible to validate any given solution derived this way.

Here are some examples of solutions that arise from anagramming:

* [http://www.zodiackillerfacts.com/forum/viewtopic.php?f=51&t=832&start=40#p13807 Small sampling from "sincos"]
* From doranchak:
** 13-letter English words that have the same letter distribution as the symbols of the cipher:
*** international, participation, concentration, interventions, investigating, participating, inappropriate, investigative, authoritarian, mediterranean, intentionally, accommodation, strengthening, commissioners, differentiate, collaborators, incorporation, unwillingness, mismanagement, superstitious, mathematician, nationalities, instantaneous, nationalistic, inconsistency, choreographer, preponderance, condescending, applicability, contingencies, indeterminate, sarcastically, temperamental, disillusioned, prerequisites, intelligences, irreplaceable, headquartered, reincarnation, proportionate, appropriating, inclusiveness, preservatives, ornamentation, uninteresting, incapacitated, contaminating, irrationality, abolitionists, improprieties, structuralist, sharecroppers, solicitations, intermarriage, arbitrariness, impermissible, disconnection, professorship, scintillating, insufficiency, spectroscopic, satisfactions
** Small sampling of 13-letter surnames that have the same letter distribution as the symbols of the cipher:
*** radhakrishnan, bhattacharjee, villavicencio, chattopadhyay, oluwatobiloba, degraffenreid, knappenberger, brandenburger, hebblethwaite, rathakrishnan, degraffenried, sahasrabuddhe, stamatopoulos, schlegelmilch, sastrowardoyo, konstantinova, muruganantham, thorsteinsson, madhusoodanan, wojciechowicz, hintermeister, klingenberger, vansteenkiste, raveendranath, blankenbiller, messerschmitt, abdollahzadeh, vlaisavljevic, stamatopoulou, giacomantonio, gebregziabher, gardarsdottir, blattenberger, agustiningsih, sverrisdottir, shirmohammadi, reichenbacher, schottenstein, christophoros, javakhishvili, sundareswaran, schiermeister, kaluhiokalani, natsvlishvili, monteferrante, ntakirutimana, derakhshandeh, winternheimer, spangenberger, liechtenstein, heiderscheidt, chandrarathne, shettlesworth
** [http://zodiackillerciphers.com/all-names-z13-list2-sorted.txt A sampling of 69,607 common first-last name combinations] that have the same letter distribution as the symbols of the cipher.
*** [http://zodiackillersite.com/viewtopic.php?p=18552#p18552 (Original broken forum link)]
* From [http://zodiackiller.21.forumer.com/viewtopic.php?t=6376 Tom Voigt]:
** knickerbocker
** [http://zodiackiller.21.forumer.com/viewtopic.php?p=120299#120299 aintgonnatell]
* From [http://www.santarosahitchhikermurders.com/ Deb Silva]:
** [http://en.wikipedia.org/wiki/Bobby_Beausoleil Bob Beausoleil]
* From Anonymous:
** Jimmy Phillips (also credited to [http://zodiackiller.fr.yuku.com/topic/3827/Jimmy-Phillips alanbenjy])
* From Christer Böke:
** Frank Frazetta ([http://zodiackillersite.com/viewtopic.php?f=63&t=1275 Tim Holt] was drawn by Frank Bollle and Frank Frazetta)
** Grant Santiago
* From [https://www.tapatalk.com/groups/zodiackillerfr/simple-solve-for-the-my-name-is-t8738.html#p145360 jaydeezodiachunter]:
** Debbie Faraday

= Solutions that fit if you relax other constraints of the cipher =

Solutions that fit if you allow all three "circled 8" symbols to be wildcards:
* From Michael Kelleher:
** thebigsecrete
Solutions that are produced via multiple operations:
* From [http://www.zodiackillerciphers.com/?p=46 Lyndon Lafferty]:
** NAME GRANT, or NAME IS GRANT
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/detailed-solution-to-z13-and-z32/ Faycal Ziraoui's solution]
A solution that applies the 408 key and interprets some symbols as nulls:
* from [http://zodiackiller.fr.yuku.com/topic/6839/Zodiacs-Name-using-408-Key Rembrandt]:
** ED SHAW
Solutions with one name part in the middle, and another name part split in half and written backwards:
* [http://www.zodiackillersite.com/viewtopic.php?p=69126#p69126 DEBBIE FARADAY]

= Other interpretations =

* "My name is" contains 8 letters. The cipher text contains 8 letters and 5 special symbols. The special symbols contain Zodiac's name and the rest just mean "My name is" (Source: Jeppesen)
* [https://www.tapatalk.com/groups/zodiackillerfr/general-book-discussion-for-hunted-the-zodiac-murd-t10141.html#p197345 "Set addition" interpretation of Z13 by Doug Oswell], resulting in solution: "FROM TED KACZYNS[K]I"
* [https://www.tapatalk.com/groups/zodiackillerfr/paul-astrup-s-theory-meteorological-symbols-challe-t10261.html#p202558 Weather symbols]
* The line after "My name is" is roughly above symbols that resemble "Tom" spelled backwards. (Source: David Cauley via YouTube comments)

Encyclopedia of observations

2023-12-16T12:34:00Z

Admin: /* Z13 */

This page is meant to collect the many factual observations and studies people have made about the ciphers over the years. It is a work in progress.

= Z408 =
== Ngram observations ==
* Cipher contains 62 repeated bigrams [http://zodiackillerciphers.com/images/z408-repeating-bigrams.png (illustration)], 11 repeated trigrams [http://zodiackillerciphers.com/images/z408-repeating-trigrams.png (illustration)], and 2 repeated quadgrams [http://zodiackillerciphers.com/images/z408-repeating-quadgrams.png (illustration)].
** In a test of 1,000,000 random shuffles, none had 62 or more repeated bigrams [http://zodiackillerciphers.com/images/z408-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 27.
** In a test of 1,000,000 random shuffles, none had 11 or more repeated trigrams [http://zodiackillerciphers.com/images/z408-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.5.
** In a test of 1,000,000 random shuffles, 249 (0.025%) had 2 or more repeated quadgrams [http://zodiackillerciphers.com/images/z408-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.0095.
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 182, and has length 100 [http://zodiackillerciphers.com/images/z408-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0185. This is 4.6% smaller than the IoC of Z340.
* IoC divided by cipher length (408) is 0.00004534. This is 21% smaller than the IoC per length value for Z340 (Source: Jarlve)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z408 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]

== Repeated symbols by columns and rows ==
* The 408 cipher has 6 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, 0.23% of shuffled ciphers had at least 6 rows with no repeated symbols [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z408-shuffles-rows-without-repeated-symbols (raw data)]
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* Several homophone cycles show improved regularity when transcription errors are corrected in the ciphertext (see below)
* The homophone cycle sequence for plaintext letter "L" is not as regular as cycle sequences for other common letters (i.e., his symbols assignments for plaintext "L" were more random) [http://zodiackillerciphers.com/408/key.html#4 (More details on cycles)] The Hardens said they guessed Zodiac would have used the word KILL repeatedly, and an enciphered bigram representing LL occurs 6 times in the cipher text. Perhaps a more regular cycle for L, involving more symbols, would have thwarted this guess by the Hardens.
* Many of the highly regular homophone cycles break down in Part 3 of the cipher text for some unknown reason [http://zodiackillerciphers.com/408/key.html#4b (More details)]
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://zodiackillerciphers.com/images/Homophonic%20Cycles%20z408.pdf Largo's analysis of regularity of homophone cycles]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Other observations ==
* The last 18 letters of the 408 decode to a sequence of gibberish: EBEORIETEMETHHPITI
* Many symbols among the last 18 symbols are found directly above in the same columns. The "QEHM" sequence is particularly noteworthy. [http://zodiackillerciphers.com/images/last-18-filler.png (Image)] (Source: glurk)
** In both Part 1 and Part 3 of the cipher, the QEHM sequence occurs in the exact same location. [https://www.tapatalk.com/groups/zodiackillerfr/ebeorietemethhpiti-t550.html#p147047 (Source: DerekP)]
** [https://www.tapatalk.com/groups/zodiackillerfr/408-final-18-as-filler-t10792.html#p237272 Cragle's observations]
* There are misspelled words in the plaintext when the Harden key is applied. When some words are corrected, the symbols assigned to the corrected plaintext letters often resemble the symbols assigned to the original erroneous plaintext letter. [http://zodiackillerciphers.com/images/David%20Oranchak%20-%20Zodiac%20presentation-12.jpg (Image)]. Several homophone cycles show improved regularity when these corrections are made [http://zodiackillerciphers.com/408/key.html#4 (More details)]
* Several symbol/letter assignments in the 408 key seem to reflect adjacencies on QWERTY-layout keyboards (the standard keyboard layout for typewriters and computer keyboards). [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2419 (Source)]
** Statistical tests by _pi and Finder, [http://zodiackillersite.com/viewtopic.php?p=82122#p82122 summarized by Jarlve]
* Some plaintext appears to be missing directly in the boundary between Parts 2 and 3 of the cipher ("ALL THE ???? I HAVE KILLED WILL BECOME MY SLAVES") [http://zodiackillerciphers.com/408/key.html#1 (Annotated plaintext)]
* [http://zodiackillerciphers.com/408/key.html#2 More details on errors in the cipher text and on the Hardens' key]
* The "Concerned Citizen" key, sent to Sgt. Lynch of Vallejo PD 2 days after the Hardens' solution was published, contained some differences from the Hardens' key [http://zodiackillerciphers.com/408/key.html#5 (More details)]
* "All roads lead to E" phenomenon of the key [http://www.zodiackillersite.com/viewtopic.php?f=81&t=2751#p41933 (Explanations and details)] [http://zodiackillerciphers.com/images/all-roads-1.jpg (Image 1)] [http://zodiackillerciphers.com/images/all-roads-2.jpg (Image 2)]
* Adjacent sequences in the 408's key [http://www.zodiackillersite.com/viewtopic.php?p=41986#p41986 (More info)]
* Some symbols in the 408 were not reused in the 340's alphabet [http://zodiackillerciphers.com/images/new-to-z408.png (Image)]
* Zodiac made three statements about the cipher's parts:
** ''Vallejo times: Here is a cyipher or that is part of one. The other 2 parts have been mailed to the S.F. Examiner + S.F. Chronicle.''
** ''SF Examiner: Here is a cipher or that is part of one. The other 2 parts are being mailed to the Vallejo Times + S.F. Chronicle.''
** ''SF Chronicle: Here is a part of a cipher the other 2 parts of the cipher are being mailed to the editors of the Vallejo Times + SF Examiner.''
** Speculation: The following interpretation of the above statements suggests how the parts should be ordered: "Vallejo Times is listed first twice and is the first part. SF Examiner is listed first once and is the second part. SF Chronicle is listed last twice and is the third part." [http://www.zodiackillersite.com/viewtopic.php?t=3794&p=62667#p62667 (Source: Jarlve)]
* The plaintext solution has a shorter average word length than regular English (4 vs 5) (Source: [http://www.zodiackillersite.com/viewtopic.php?t=4204&p=68848#p68848 Jarlve and beijinghouse])
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* Of the three letters sent to newspapers, only the Chronicle's letter said "In this cipher is my identity". This could be interpreted as referring specifically to the cipher portion the Chronicle received, which is the end portion of the cipher which also contains the unsolved 18 characters at the end. Perhaps Zodiac is implying his identity or name can be derived from this portion or the last 18 characters. [https://discord.com/channels/996952324150931477/996952376894292018/1087499591651438612 (Source: Nicodemus)]

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z408 reveals a spike of 18 repeats at shift of 49
** Among 1,000,000 random shuffles, only 2.2% of them had a spike as good or better as the one observed in Z408 [http://www.zodiackillersite.com/viewtopic.php?p=48226#p48226 (details)]
* The 408 at period 4 transposed or period 102 untransposed has an even more significant (than Z340's) doublet peak. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=73882#p73882 Jarlve])

= Z340 =
== Ngram observations ==
* Cipher contains 25 repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (illustration)], 2 repeated trigrams [http://zodiackillerciphers.com/images/z340-repeating-trigrams.png (illustration)], and 0 repeated quadgrams.
** In a test of 1,000,000 random shuffles, 110,147 (11%) had 25 or more repeated bigrams [http://zodiackillerciphers.com/images/z340-bigram-shuffles.png (Plot of distribution)], and the average number of repeats was 20.
** In a test of 1,000,000 random shuffles, 67,573 (7%) had 2 or more repeated trigrams [http://zodiackillerciphers.com/images/z340-trigram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.4.
** In a test of 1,000,000 random shuffles, 7,857 (0.8%) had at least one repeated quadgram [http://zodiackillerciphers.com/images/z340-quadgram-shuffles.png (Plot of distribution)], and the average number of repeats was 0.008.
** The count of 25 repeating bigrams seems low compared to the average for ciphers with similar IOC generated during experiments [http://www.zodiackillersite.com/viewtopic.php?p=55893#p55893 (Source)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 5-gram repeating fragments study]
* The IOF trigram repeats in the same columns, and are spaced 8 lines apart, reminiscent of the 8-line height of each of the original 3 parts of the 408 cipher (from Tahoe27). [http://zodiackiller.fr.yuku.com/reply/97203/Back-to-Basics-patterns-of-symbols#reply-97203 (Illustration)] [http://zodiackillersite.com/viewtopic.php?p=41771#p41771 (Illustration)]
* TODO: Multidirectional ngram study (including multiple distances, and repeating fragments)
* TODO: Periodicity of repeating fragments study
* Reading the cipher text from left to right and top to bottom, the longest sequence containing no repeated bigrams starts at position 168, and has length 123 [http://zodiackillerciphers.com/images/z340-longest-sequence-with-no-repeated-bigrams.png (Illustration)]
* TODO: periodic ngram / fragment test of individual halves of the 340 (horizontally and vertically), as well as individual "even/odd" transformations.
* Near the end of line 2, K and backwards F appear. Near the beginning of line 19, F and backwards K appear, perfectly mirroring the symbols on line 2. There is an additional symmetry in their placement as corners of the inner box. [http://zodiackillerciphers.com/images/fk-pattern-symmetry-inner-box.png (Illustration)] (by GC)
** The corrected K on line 6 is also next to an F. Does this carry any significance? [http://www.zodiackillersite.com/viewtopic.php?p=71188#p71188 (Source: druzer)]
* The ngram BOUTME appears in both the 1st and 2nd nine-line sections of Z340 after applying the substitution key and lining up the rows to read by columns [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237007 (Source: rando)]
=== Unigrams ===
* Index of Coincidence (IoC) of the cipher is 0.0194. This is 4.9% larger than the IoC of Z408.
* IoC divided by cipher length (340) is 0.00005706. This is 26% larger than the IoC per length value for Z408 (Source: Jarlve)
* If you highlight all occurrences of certain symbols, they seem to avoid the middle of the cipher text.
** Specific example: Some symbols are exclusive to the first 6 and last 6 rows. An unusual number of symbols are missing from the middle 8 rows. [http://www.zodiackillersite.com/viewtopic.php?p=56330#p56330 (1)],[http://zodiackillersite.com/viewtopic.php?p=53902#p53902 (2)] (Source: Jarlve, smokie treats)]
* [http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations#Kasiski_Examination_2 Kasiski examination of the 340]
* Column unigram bias: Certain column combinations seem to be biased towards certain symbols. [http://www.zodiackillersite.com/viewtopic.php?p=56155#p56155 (Source: Jarlve)] (See also: Z13 even/odd bias below)
* Some symbols are [http://www.zodiackillersite.com/viewtopic.php?p=56193#p56193 unusually clustered or unusually spread apart].
** Compared to shuffles, Z340 has slightly more than expected [http://www.zodiackillersite.com/viewtopic.php?p=56277#p56277 outliers of unusually distributed symbols.]
** Some groups of symbols only appear in pairs of small regions [http://www.zodiackillersite.com/viewtopic.php?p=56609#p56609 (Source)]
** Symbols that exhibit regional bias seem to avoid being involved with perfect cycles [http://zodiackillersite.com/viewtopic.php?p=61675#p61675 (Source: smokie treats)]
** Some circles and circle-like symbols seem clustered together. [http://www.zodiackillersite.com/viewtopic.php?p=82148#p82148 (significance test)]
* When counting unique sequences by length, there is a very unusual spike of 26 sequences of length 17. When counts are plotted in a histogram, there is a steep drop off after length 17. The cipher has 17 columns. [http://zodiackillersite.com/viewtopic.php?p=50804#p50804 (Source: jarlve and smokie treats)]
* The 20 new symbols in Z340 that aren't in Z408 represent about 80 characters in the cipher. In other words, almost 1/4th of the cipher is represented by symbols not used before [http://www.zodiackillersite.com/viewtopic.php?p=64822#p64822 (Source: Hubert J. Bernhard)]
** I counted 16 symbols that are new to Z340 (about 25% of the size of the cipher alphabet) [http://zodiackillerciphers.com/wiki/images/7/76/Comparison-z-alphabets.jpg (illustration)]
** I counted 77 occurrences of symbols that are new to Z340 (about 23% of the ciphertext) [http://zodiackillerciphers.com/images/all-the-new-symbols-in-z340.png (illustration)]
* The 340 is 68 symbols shorter than the 408. That is a 16.7% decrease. The 340 has 63 distinct symbols, compared to the 408's 54 distinct symbols. This increase is the same percentage, 16.7%. (Source: Mike Cole)
* There may be a spike in period 16, 32, and 48 unigrams, which also involve the symbols in the "pivots" ([http://zodiackillersite.com/viewtopic.php?p=67145#p67145 Source: smokie treats [1]]) [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* "L" symbols tend to [http://www.zodiackillersite.com/viewtopic.php?p=71190#p71190 favor a particular side of the cipher text] (source: doranchak)
** Somwhat similar effect is seen with Vs and upside down Vs [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 (source: TheMist)]
** Regarding the "L"s, the ones in the top half tend to line up in columns [http://www.zodiackillersite.com/viewtopic.php?p=71195#p71195 (source: Mr. lowe)]
** [http://www.zodiackillersite.com/viewtopic.php?p=71201#p71201 Additional observations of related symbols, by TheMist]
*** Looking at the triangles, the top of the half has the sequence: Full, empty, full, empty. The bottom half has: empty, full, empty, full.
*** The diagonally half-filled squares have the sequence: Right, left, left, left; right, left, left, left.
*** The 3 P symbols are each separated by 4 reversed P symbols.
* Symmetry of related symbols [http://www.zodiackillersite.com/viewtopic.php?p=71249#p71249 (source: Druzer)]
* For almost every V, an upside-down V can also been found on the same line. (source: [http://zodiackillersite.com/viewtopic.php?p=78004#p78004 doranchak], [http://www.zodiackillersite.com/viewtopic.php?p=71200#p71200 TheMist])
* Many of the < and > symbols form a smooth curve pattern. [http://zodiackillersite.com/viewtopic.php?p=78005#p78005 (source: doranchak)]
* [http://zodiackillersite.com/viewtopic.php?p=60359#p60359 Symbols in symbol order, for handwriting comparison (source: Fisherman'sFriend)]
* There is a symmetry to the "V" and "<" (rotated "V") symbols [http://zodiackillersite.com/viewtopic.php?p=79445#p79445 (source: Zwick808)]
* A backwards J symbol appears in the 6th column, just as it does in Z408 and Z32 [http://www.zodiackillersite.com/viewtopic.php?p=79929#p79929 (source: Jelberg)]

=== Unusual biases in the number of bigram repeats ===
==== Top half / bottom half bias ====
* The lower left of the cipher text seems to contain very few repeated bigrams [http://zodiackillerciphers.com/images/z340-repeating-bigrams.png (see illustration)]
** The largest rectangular region that contains no repeats has dimensions 5x10. It covers an area of 50 positions (14.7%) of the cipher.
** Largest rectangular regions were found for 1,000,000 shuffles. 22% of them had ngram-free rectangular areas of size 50 or higher. [http://zodiackillerciphers.com/rectangular-regions-with-no-bigrams-results.txt (details)]
* The top half of the cipher text, considered on its own, contains 9 repeated bigrams. However, the bottom half of the cipher text, considered on its own, contains only 1 repeated bigram.
** In 1,000,000 shuffles, only 2.4% of them had halves with a repeated bigram discrepancy as large as the one observed in the 340 (i.e., a difference of at least 8 repeated bigrams between the halves).
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-halves.png (Distribution of repeated bigram discrepancy among shuffles)]
** By contrast, the 408's top half has 17 repeated bigrams and its bottom half has 14.
** If you omit the last column of Z340, the bottom half of the cipher contains zero repeating bigrams. [http://zodiackillersite.com/viewtopic.php?p=64790#p64790 (doranchak)]

==== Even / odd position bias ====
* The cipher text also shows a bias in repeated ngram counts within even positions and odd positions.
** If you remove all symbols that are in even-numbered positions, there are only 2 repeated bigrams.
*** In this case, there are also 0 repeated trigrams.
** If you remove all symbols that are in odd-numbered positions, there are 10 repeated bigrams.
*** In this case, there are also 2 repeated trigrams.
** [http://zodiackillerciphers.com/images/z340-even-odd-bias.jpg (Illustration)]
** The difference in bigram repeats between both cases is 8. During shuffle tests, the difference was 8 or higher in only 2.4% of shuffles. This is the same difference and percentage found for the top half / bottom half bias.
** [http://zodiackillerciphers.com/images/z340-shuffles-bigram-spread-between-even-odds.png (Distribution of repeated bigram discrepancy among shuffles)]
** In the unmodified 340, there is a "box corner" pattern that repeats. After removing all symbols falling on odd-numbered positions, repeating trigrams appear where the box corner patterns were observed.
*** [http://zodiackillerciphers.com/images/z340-box-corners-appearing-as-trigram.png In this illustration], the box corners are highlighted in green on the left. The repeating trigrams are shown on the right, highlighted in purple. Note the repeating sequence "O, half-filled square, C" that is seen in both cases.
*** Similar repeating patterns can be also found [http://www.zodiackillersite.com/viewtopic.php?p=39772#p39772 (illustration)]
** 58 unique symbols fall on odd positions (5 symbols missing). 54 symbols fall on even positions (9 symbols missing). The 14 symbols that aren't shared comprise 22% of the 63 total symbols. [http://www.zodiackillersite.com/viewtopic.php?p=39002#p39002 (Source: daikon)]

==== Periodic ngram bias ====
* Consider the normal way of counting bigrams (one symbol right next to another). Let's call this "period 1" bigrams, because the symbols are one position apart. There are 25 repeating period 1 bigrams. But at other periods, there is a higher count of repeating bigrams. In fact, at period 19, there are 37 repeating bigrams. [http://zodiackillerciphers.com/images/z340-period-19-bigram-samples.jpg (Illustration of a small sample of repeating period 19 bigrams)]
** Daikon's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=39003#p39003 (Original broken link)]
*** [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (Wayback snapshot)]
*** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ (Live version)]
** Jarl's original observation:
*** [http://www.zodiackillersite.com/viewtopic.php?p=38542&sid=c94f602c513bea38e12605b93b03c883#p38542 (Original broken link)]
*** [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (Wayback snapshot)]
*** [https://zodiackiller.net/community/postid/39170/ (Live version)]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width17.png Repeating period 19 bigrams highlighted in the cipher text]
** [http://zodiackillerciphers.com/images/z340-period19-bigram-repeats-width19.png The same, but easier to spot when cipher is written into 19 columns]
** A test of 1,000,000 random shuffles suggests a 1 in 216 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** If you look at all periods from 2 to 170, 34 of them have 25 or more repeating bigrams. In other words: 20% of other periods have equal or better repeating bigram response than period 1.
* Also, if you flip the ciphertext horizontally (horizontal mirroring), a higher peak occurs at period 15, which produces 41 repeating bigrams. This is consistent with the phenomenon that normal (period 1) bigrams have more repeats when the cipher text is flipped horizontally.
** A test of 1,000,000 random shuffles suggests a 1 in 12821 chance that this is happening by chance [http://www.zodiackillersite.com/viewtopic.php?p=46618#p46618 (More info)]
** A second peak of of 34 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 29.]
** A third peak of 33 repeating bigrams [http://zodiackillersite.com/viewtopic.php?p=42987#p42987 occurs at period 100.]
* Other manipulations that lead to high numbers of bigrams:
** Various row-wise and column-wise offsets and periodic operations [http://www.zodiackillersite.com/viewtopic.php?p=56059#p56059 lead to between 41 and 45 bigrams.] (found by Jarlve and doranchak) (The column offset operation leading to 45 bigrams [http://www.zodiackillersite.com/viewtopic.php?p=67018#p67018 appears to be significant])
*** [http://www.zodiackillersite.com/viewtopic.php?p=76741#p76741 Jarlve's analysis of chances that a random cipher, having 37 repeating bigrams at period 19, would jump to 45 with a column offset]
** Column period 2 combined with linear period 18 produces 44 repeating bigrams [https://zodiackillersite.com/viewtopic.php?p=50504#p50504 (doranchak)]
** Shift operations combined with periodic untransposition and mirroring [http://zodiackillersite.com/viewtopic.php?p=55478#p55478 leads to 48 bigrams and 8 trigrams.] (found by Largo)
** [http://www.zodiackillersite.com/viewtopic.php?p=67042#p67042 Visualization of bigrams formed via shift operation combined with periodic untransposition (source: Largo)]
** [http://zodiackillersite.com/viewtopic.php?p=76751#p76751 "The simplest way to bring the high period 19 results together is columnar odds evens and then raise each column up one space." (Mr. Lowe)]
* [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts.png Plot of periodic bigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-bigram-counts (Raw data: Period, # of repeated bigrams in normal 340, # of repeated bigrams in mirrored 340)] [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot)]
* [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts.png Plot of periodic trigram counts in normal and mirrored cipher texts] [http://zodiackillerciphers.com/images/z340-periodic-trigram-counts (Raw data: Period, # of repeated trigrams in normal 340, # of repeated trigrams in mirrored 340)]
* Repeated quadgrams appear only at periods 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (illustration)] and 116 [http://zodiackillerciphers.com/images/z340-4gram-at-period-116.png (illustration)]. They do not appear when considering the mirrored ciphertext.
* A repeated 5-grams appears at period 101 [http://zodiackillerciphers.com/images/z340-5gram-at-period-101.png (Illustration)]
* Bigram peaks still seem to appear even if you filter out the effects of the symbols that occur 10 or more times [http://www.zodiackillersite.com/viewtopic.php?p=42996#p42996 (Jarlve's plot - it's the second one there)]
* [http://www.zodiackillersite.com/viewtopic.php?p=42947#p42947 Jarlve's repeating fragment measurements] seem to correlate strongly with periods 19 (normal cipher) and 15 (mirrored cipher).
* [http://www.zodiackillersite.com/viewtopic.php?p=43645#p43645 Inserting a randomized column causes a 40 bigram peak to occur at period 5] [http://www.zodiackillersite.com/viewtopic.php?p=44258#p44258 (see also)]
** [http://www.zodiackillersite.com/viewtopic.php?t=4902&p=80200#p80200 (More experiments / analysis)]
* TODO: Jarlve's "symbol expansion" test, higher ordered ngrams and fragments
* TODO: how often does a random shuffle show a period that has repeated quadgrams/5grams?
* [http://zodiackillerciphers.com/period-19-bigrams/ Visualization tool showing effects of various transposition schemes on bigram/trigram/fragment counts]
* [http://zodiackillerciphers.com/period-calculator/ Period calculator - A way to visualize the relation of periods to mirrored counterparts, and the effect of untransposition on the interesting patterns (pivots, box corners, and repeating bigrams)]
* Z408 has more period 2 bigrams than expected, while Z340 has fewer than expected [http://www.zodiackillersite.com/viewtopic.php?p=62928#p62928 (Source: Jarlve)]
* "Mirror immunity": The number of repeating bigrams is resistant to mirroring operations [http://www.zodiackillersite.com/viewtopic.php?p=65154#p65154 (source: Largo)]
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3591 Jarlve's summary of operations leading to "special bigram peaks" of 41, 44, and 45]
** [http://www.zodiackillersite.com/viewtopic.php?p=65292#p65292 Largo's shift operation that produces 45 bigrams and 4 trigrams at period 19]
* "Herringbone patterns" (Source: smokie treats) [http://zodiackillersite.com/viewtopic.php?p=67145#p67145 [1]] [http://zodiackillersite.com/viewtopic.php?p=70670#p70670 [2]]
* Periodic ngram peaks resulting from "crossed line" transposition [http://www.zodiackillersite.com/viewtopic.php?p=70155#p70155 (Source: Largo)]
* The use of sequential homophones is a possible explanation for the appearance of periodic outliers [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]
* A repeating 6-gram can be found when un-transposing certain rows at period 10 [http://www.zodiackillersite.com/viewtopic.php?p=81513#p81513 (Source: Largo)]

==== Other ====
* A large block in the 2nd half of the cipher has zero repeating bigrams [http://www.zodiackillersite.com/viewtopic.php?p=64790#p64790 (Source: doranchak)]

== Repeated symbols by columns and rows ==
* The 340 cipher has 9 rows that each contain no repeated symbols [http://zodiackillerciphers.com/images/z340-z408-repeated-symbols-by-rows-and-columns.jpg (Illustration. Rows are marked in yellow.)] In 1,000,000 shuffles, no shuffled cipher text had at least 9 rows with no repeated symbols [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols.png (plot of distribution)] [http://zodiackillerciphers.com/images/z340-shuffles-rows-without-repeated-symbols (raw data)]
* If you split the cipher in half with a horizontal cut in the middle, the top and bottom halves each start with 3 lines that have no repeated symbols. This symmetry is discussed in [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson Dan Olson's analysis].
* Every column contains at least one repeated symbol.

== Homophone cycles ==
* [http://zodiackillersite.com/viewtopic.php?p=47686#p47686 Tests of cycle significance with shuffle experiments]
* [http://www.zodiackillersite.com/viewtopic.php?p=50869&sid=b6d8535141b9a404e45545684cac7ffe#p50869 Longest-repeating substring search for cycles, compared to shuffles]
* Homophone cycles seem to be present but with much weaker regularity than the cycles of Z408.
* [http://www.zodiackillersite.com/viewtopic.php?p=54990#p54990 Removing row 14 causes significant improvement in perfect cycles (Jarlve)]
* Other "irregular" types of cycles are present in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=56608#p56608 (Raw results and examples)]
* When comparing all possible ways that length 6 cycles involving 2 symbols can appear, Z408 and Z340 [http://www.zodiackillersite.com/viewtopic.php?p=65920#p65920 seem to show very similar behavior.] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4099&p=66225 Evidence of increasingly random cycles in Z408 and Z340] (source: Jarlve)
* [http://www.zodiackillersite.com/viewtopic.php?p=66500#p66500 Decreasingly random cycles, for both Z408 and Z340, peak when the cipher is shifted 11 rows downwards] (source: Jarlve)

== Kasiski Examination ==
* A Kasiski examination performed on unigrams in Z340 reveals a spike at shift of 78 [http://www.zodiackillersite.com/viewtopic.php?p=48147#p48147 (Source: Bart Wenmeckers)].
** The pivot patterns turn into repeating bigrams at period 39. The number 39 is exactly half of 78. And half of 39 is tantalizingly close to 19, which is the period that produces the peak number of repeating bigrams.
** 26 is a factor of 78 (There are 26 letters in the English alphabet)
** Application of Z408's key to Z340 results in a "plaintext" that still retains a Kasiski examination spike at shift of 78.
** Among 1,000,000 random shuffles, only 0.28% of them had a spike as good or better as the one observed in Z340 [http://www.zodiackillersite.com/viewtopic.php?p=48225#p48225 (details)]
** For shift values of 2 through 6, the number of repeats is unusually low (1 or 2). [http://www.zodiackillersite.com/viewtopic.php?p=48176#p48176 (source)]
** [http://zodiackillerciphers.com/period-78-unigram-repeats/ Visualization of peak at shift 78 by viewing as doubles in untransposed period 78] [http://zodiackillerciphers.com/period-78-unigram-repeats/index-with-pivots.html (with pivots highlighted)]
** [http://zodiackillerciphers.com/images/width-26-z340-kasiski.png The doubles are easier to see when Z340 is transcribed to width 26]
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78. [http://www.zodiackillersite.com/viewtopic.php?p=48212#p48212 (Source: Bart Wenmeckers)]
** When looking at normalized means of columnar IoC, resonances at multiples of 5 are observed. [http://www.zodiackillersite.com/viewtopic.php?p=48442#p48442 . (Source: doranchak)]
** The use of sequential homophones is a possible explanation for the spike in doublets at offset 78 [http://www.zodiackillersite.com/viewtopic.php?f=81&t=4806 (Source: Jarlve)]

== The "Pivots" ==
* The 340 contains a pair of intersecting repeating trigrams. We refer to each repeating trigram as a "pivot". [http://zodiackillerciphers.com/wiki/index.php?title=Pivots Illustration and analysis] (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010, and Smithy)]
* These anomalies both occur 4 columns in from the side and one column from the center. (Source: [http://www.zodiackillersite.com/viewtopic.php?f=81&t=323 bentley, 2010)]
* The pivot patterns become repeating bigrams if you rewrite the cipher text at period 39.
** When calculating column IoC at different column widths, spikes are observed at widths 39 and 78 (see Kasiski examination section above)
** When numbering the cipher text from 1 to 340, the intersections of the pivot patterns fall on positions 195 and 234, which are 39 positions apart. Interestingly, 195 and 234 are both evenly divisible by 39. [http://www.zodiackillersite.com/viewtopic.php?p=51239&sid=02e2094bcfebe5f9f14dc9da8c0a7ea8#p51239 (source)]
* Similarly, the pivot patterns become repeating bigrams if you mirror the cipher text horizontally and rewrite it at period 29.
** Period 29 is the 2nd highest periodic bigram peak for the mirrored 340 (see the Periodic ngram bias section above)
* In an experiment, the 340 was randomly shuffled over 41 million times. A pair of pivots that point in the same direction was only observed in about 1 in 237,000 shuffles.
* In [http://www.zodiackillersite.com/viewtopic.php?f=81&t=3236#p51034 this study] the 340 was shuffled and the number of repeating bigrams was fixed at a set number. Transposition was performed and pivot pairs were counted. The results show that higher bigram counts cause pivot pairs to be created more often, but they are still rare.
* The reversed B symbols occurs only three times and cluster around the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=56610#p56610 (Source: Largo)]
* Diagonal lines drawn through the forward slash symbols "boxes in" the pivots. [http://www.zodiackillersite.com/viewtopic.php?p=59012#p59012 (Source: Biz)]
* Other repeating pairs of symbols near the pivots are suggestive of possible "incomplete" pivots. [http://zodiackillersite.com/viewtopic.php?p=73621#p73621 (Source: Largo)]
* The plus and filled in circle symbols repeat in the same positions relative to each pivot. [http://zodiackillersite.com/viewtopic.php?p=81465#p81465 (Source: Mr lowe)]
* In light of the known solution and transposition steps, the pair of pivots vaguely resembles arrowheads suggestive of the reading direction.

== Observations related to the discovered plaintext and encipherment method ==
* "BELLI" (as in Melvin Belli) appears in reverse in the 2nd to last line of the raw plaintext, before word reversals are applied. (Source: [http://www.zodiackillersite.com/viewtopic.php?p=82822#p82822 Shawn])
* The name "BEN REECE" appears in a cross formation in the raw plaintext. (Source: [https://www.tapatalk.com/groups/zodiackillerfr/new-york-times-i-ve-cracked-zodiac-a-french-engine-t9721-s20.html#p167112 Shawn-z])
* "If you have a tool or device for reading the message or key that has holes in it or something you can wrap around a device that is the key with diagonal holes. If the holes are diagonal, they will meet at the corners and the device will be weak where the corners meet. If you go down and over two spaces, there is plenty of material left between the holes at the corners and so the device can be solid." (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "First plain word of the first section HER, First line of second section LIFE IS. Could the cipher have been designed to leave these in the plain to indicate that the cipher is divided into two section, it would be interesting to see if HER or LIFE IS was used to make the key" (Source: Myron Walker, via YouTube comment on LCZ episode 6)
* "I think the last two lines were there to help find the key. That's why they were not transposed" (Source: Myron Walker, via YouTube comment on LCZ episode 9)
** Note: A solver could have focused on just those two lines, but the multiplicity is too high (88.2%). So there probably aren't enough repeats to find a unique plaintext.
* In the last 4 lines of the cipher, a 6-symbol section decodes to "HARDEN" (reference to the Hardens) when the symbols are individually reversed. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237444 (Source: rando)]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780-s10.html#p237846 More fragments that appear using the same technique]
** [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-z408-t10802.html#p237932 Results for Z408]
* The untransposed plaintext has a 13-character section beginning with A and ending with M. Z13 also begins with A and ends with W. [https://www.tapatalk.com/groups/zodiackillerfr/curiosities-t10780.html#p237455 (Source: cragle)]

== Other observations ==
* Application of 408's key to the 340:
** Applying the 408's key to the 340 [http://www.zodiackillersite.com/viewtopic.php?t=3970&p=64238#p64238 produces this plaintext.]
** The words [http://www.zodiackillersite.com/viewtopic.php?p=76278#p76278 "NET NULL"] appear
** Per FBI, applying the 408's key yields plaintext frequencies similar to expected English plaintext (source: [https://www.evernote.com/l/AAHhLm_9uz5Lrr67cwPc4bXS1z9XXxylNPk FBI case files])
* Some symbols in the 340 were not in the 408's alphabet [http://zodiackillerciphers.com/images/new-to-z340.png (Image)]
* The paper the cipher is written on contains several [http://oranchak.com/340-5th-avenue.jpg Fifth Avenue watermarks] (here's [http://zodiackillerciphers.com/images/i1x1W.gif glurk's animation] to help you spot where they appear).
* The first 3 symbols of the 340 do not reappear soon. It starts with "HER", and H only appears 3 other times, E only appears 2 other times. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24573#p24573 Duman])
* In the third column, the 3 occurrences of the "R" symbol are evenly spaced, each separated by four rows. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=22619#p22619 Wrench])
* The author of the cipher does not use the forward-facing letter Q as a cipher symbol, but uses a backwards-facing Q instead. Similarly, he does not use the forward-facing letter C as a cipher symbol in the 408-character cipher, but uses a backwards-facing C instead. Why doesn't he use up all the normal alphabetic symbols before resorting to additional symbols and variations? [http://www.zodiackillersite.com/viewtopic.php?p=48685#p48685 (one possible explanation)]
* The first repeated symbol occurs at the 19th position. Thus the first 18 symbols contain no repeats. Coincidentally, the last 18 symbols of the 408 cipher do not form a legible solution. (From [http://www.zodiackillerfacts.com/forum/viewtopic.php?p=24901#p24901 traveller1st])
* The most frequently occurring symbol, +, occurs 24 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. Also both occurrences of the X symbol fall on prime positions against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)] (TODO: Prime phobia distribution study for all symbols)
** [http://www.zodiackillersite.com/viewtopic.php?p=43740#p43740 Possible schemes that increase probability of natural appearance of this phenomenon]
* The second most frequently occurring symbol, B, occurs 12 times. Only once does it fall on a prime-numbered position in the cipher text (counting from 1 to 340), against expectations. [http://www.zodiackillerciphers.com/?p=319 (More detail)] [http://zodiac340.blogspot.com/2013/03/zodiac-primes.html (From Dan Johnson)]
* The upper loop of the "B" symbol on line 19 column 9 is larger than the lower loop, making the symbol look disproportional and distinct from the other "B" symbols. (From Doc. Doc also speculates the symbol was original a "P" and the author corrected it by adding the bottom loop.)
* The last occurrence of the "+" symbol is wider than the others. (From Doc. Doc speculates that the author "hesitated" on this symbol.)
* Cipher symbols seem to get larger as the cipher goes on. Row 20 seems larger than Row 1. (From Doc. Doc speculates the author wrote the cipher from top to bottom, and was tiring.)
* The backwards D at the end of the first line [http://zodiackillerciphers.com/images/z340-d-dot-line-1.png appears to have a dot in it] (Source: [http://boxofrain.wordpress.com/2007/08/12/zodiac-killers-unsolved-340-symbol-cipher/#comment-6572 comment from "The McNX"])
* The symbols that represent "R" in the 408 are [[File:br.jpg]] and [[File:backslash.jpg]]. Both symbols are missing from the 340 cipher. (Source: [http://zodiackillersite.com/viewtopic.php?p=9091#p9091 Wier])
* The symbol '+' is frequently adjacent (in all directions, not just left/right) to the symbol 'R'. (Source: http://www.zodiackillersite.com/viewtopic.php?p=39791#p39791). 'B' is the 2nd most common symbol in the cipher (12 appearances), but for some reason it is adjacent to only one of the 24 '+' symbols.
* The average of the position numbers for all occurrences of the '+' symbol is 171, which is only one position from the midpoint of the cipher. This suggests the + symbols are very uniformly distributed throughout the ciphertext. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* The '+' symbol does not seem to cycle well with other symbols. [http://www.zodiackillersite.com/viewtopic.php?p=43059#p43059 (Source: Jarlve)]
* A tiny 'R' is written at the bottom right corner of the page. Similarly, information is written at the bottom right corner of a [http://zodiackillerciphers.com/wiki/images/6/67/1bcdefg_-_ZODIAC_-_July_69_Cipher_part_3_SF_Examiner.jpg section of the 408], and the bottom right corner of the [http://zodiackillerciphers.com/wiki/images/3/31/9a_-_San_Francisco_Chronicle_Map_Code_letter_June_26_1970_Color_High_Res.jpg letter containing the map code.]
* [http://zodiackillersite.com/viewtopic.php?p=41166#p41166 Cycles of length 2 are biased towards odd-numbered positions in the cipher text]
* The 340 has 9 rows that each have no repeated symbols. By comparison, the 408 has 6. Moreover, in the 340, there are two triplets of rows that show symmetry about the vertical midpoint of the cipher text. See [http://zodiackillerciphers.com/wiki/index.php?title=FBI_analysis_from_Dan_Olson]. [http://zodiackillerciphers.com/images/row-repeat-comparisons.jpg (Image of row repeat comparisons)]
* A forward-K appears to be scratched out, and corrected with a backwards K symbol. [http://zodiackillerciphers.com/images/backwards-k-correction.jpg (Image)]
* The backwards K symbol is written with the slanted segments joining perfectly in the middle. But the forwards K symbol is written with the slanted segments offset from each other. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* W symbols are flared and M symbols are not. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* "I noticed that as I progressed down the grid, I was able to mostly predict some subtle features. By and large, if a symbol was reversible such as '<' or '>' or '^' or 'v' you would regularly encounter more than 1 variation of the symbol on the same line or collumn, but very rarely see straight up duplicates. The '+' symbol is, by a massive margin, the most common symbol to be seen in duplicate. As symbols which used a circle in them were used, I was more or less able to say 'I bet the next circle isn't the same as the one already on this line or collumn.' So I'd see an empty one, then a split one, then a full one, then a half shaded one... Almost as if differentiating them was an after-thought, to ensure everyone had a harder time trying to decipher it. [https://www.reddit.com/r/ZodiacKiller/comments/aqsfey/z340/egjaxam/ (Source: vtschoir)]
* From Scott Akin: All occurrences of the "H" symbol are involved with this observation: Consider the rectangular regions formed by the corners highlighted in [http://zodiackillerciphers.com/images/80-character-rectangles.png this illustration]. Each region is exactly 80 characters in size (4x20 and 5x16), and there is symmetry to the corner symbols.
** Largo's test finds that this [http://www.zodiackillersite.com/viewtopic.php?p=49653#p49653 often occurs by chance], even with random text.
* From "Haley25": Zodiac's "bus bomb letter" contains a section he highlighted which, when punctuation (except for "and" signs and the hyphen) and spaces are removed, contains exactly 340 letters. [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316.html (source)] [http://zodiackillerciphers.com/images/haley25-observation.png (illustration)]
* From Shawn: BTK's word search puzzle has exactly [http://www.zodiackillersite.com/viewtopic.php?t=885&p=54429#p54429 340 letters and numbers in it.]
* Line 11 is suggestive of the phrase "U R TO DIE BY" [http://zodiackillerciphers.com/images/u-r-to-die-by.png (Illustration)] (Source: bentley)
* Appearance of anagrams of the word "FOLD" [https://www.tapatalk.com/groups/zodiackillerfr/i-think-it-s-origami-t7664.html#p123669 (Source: forbisgaryg)] [http://zodiackillerciphers.com/images/z340-fold-anagrams.jpg (Illustration)]
* Clusters of rotationally-related symbols [http://zodiackillerciphers.com/images/z340-clusters-rotationally-related-symbols.jpg (Illustration)] (See also: "box corners" discussed above.)
* [http://www.zodiackillersite.com/viewtopic.php?t=3798&p=60359#p60359 Symbols arranged by appearance]
* The [http://zodiackillersite.com/viewtopic.php?f=55&t=137 "dripping pen"] card that accompanied the cipher contains a series of months written by Zodiac: "Des July Aug Sept Oct". This sequence is exactly 17 letters long (not including spaces), which matches the width of the Z340, Z408 and Z32 ciphers.
** Spelling the months in full without spaces, as DECEMBERJULYAUGUSTSEPTEMBEROCTOBER, is exactly 34 letters long (double 17). [http://www.zodiackillersite.com/viewtopic.php?t=3808&p=66996#p66996 (source: Marclean)]
* The dot symbols are placed higher than the midpoint of the row of symbols in which they appear. [http://www.zodiackillersite.com/viewtopic.php?p=62475#p62475 (Source: Jarlve)]
* Row spacing appears more regular than column spacing, suggesting the cipher was written out by rows. [http://www.zodiackillersite.com/viewtopic.php?p=62476#p62476 (Source: Jarlve)]
* There is extra spacing between rows 12 and 13. The smallest gap, however, appears to be between rows 13 and 14, as if to make up for the extra spacing taken between rows 12 and 13. [http://www.zodiackillersite.com/viewtopic.php?p=62473#p62473 (Source: Jarlve and doranchak)]
* Horizontal mirror of the cipher produces some coincidences with the Halloween card [https://www.tapatalk.com/groups/zodiackillerfr/three-clues-in-the-halloween-card-t8737.html#p145359 (Source: jaydeezodiachunter)]
* The symbols line up very well with each other, and fit within a perfectly rendered grid, suggesting the cipher author may have used such a grid to draft the cipher text [http://zodiackillerciphers.com/images/340-with-grid.png (Illustration 1)] [http://zodiackillerciphers.com/images/93356818_2903557999738128_2748422037398618112_n.png (Illustration 2)] (Source: Sam Blake)
* Some symbols are smudged, suggestive of the cipher author's hand passing over the fresh ink of written symbols [http://zodiackillerciphers.com/images/93117852_1398346633708036_639284475892596736_n.png (Illustration by Sam Blake)]
* Similar groupings of related symbols by quadrant [http://zodiackillersite.com/viewtopic.php?f=81&t=3196&p=79241#p79241 (Source: Cragle)]
* 340 is an [https://en.wikipedia.org/wiki/Arithmetic_number "arithmetic number"] for which the average of its divisors (1, 2, 4, 5, 10, 17, 20, 34, 68, 85, 170, 340) is exactly 63, matching the cipher's alphabet size. (Source: [https://primes.utm.edu/curios/ G. L. Honaker, Jr])
** The length of Z408 with the last 18 symbols of gibberish or filler removed is 390, which is also an "arithmetic number" whose divisors have an average of exactly 63. (Source: doranchak)
* American astronomer Vesto Melvin Slipher, noted for his analysis of [https://www.researchgate.net/publication/234395617_Spectra_of_the_Night_Sky_the_Zodiacal_Light_the_Aurora_and_the_Cosmic_Radiations_of_the_Sky Zodiacal Light], died on the day Z340 was mailed to the San Francisco Chronicle. (Source: G. L. Honaker, Jr)
* [http://zodiackillersite.com/viewtopic.php?p=84668#p84668 Comparison of Z408 key with Z340 key via shifts] (Source: upsampled)
* A sequence of symbols in the upper left corner of the cipher [https://www.zodiacciphers.com/uploads/4/9/7/1/4971630/8m_orig.gif resembles the word "cipher".]
* The accompanying card has a [http://zodiackillerciphers.com/images/do%20my%20thing%201.png section with dates, presumably denoting Zodiac's crimes.] Flipping it over [http://zodiackillerciphers.com/images/do%20my%20thing%202.png makes it resemble the phrase "L = codes"] (Source: [https://discord.com/channels/996952324150931477/996952376894292018/1084594852358004796 UK-Chris on Discord])

= Z408 and Z340 =
* "The 408 and 340 ciphers fit exactly into two standard-size pages ruled into half-inch squares. The 408 will use one page plus one inch from another page. The second page will then fit the 340 exactly." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 Jem]) (Open question: Is the 340 a continuation of the 408?)
* "An 8 1/2 X 11 inch paper divided into 1/2" squares yields 17X22 or 374 separate squares. Two pages together: 374 X 2= 748. The two ciphers together? 748 symbols." (from [http://www.zodiackillersite.com/viewtopic.php?f=81&t=296 entropy])
* [http://zodiackillerciphers.com/images/z340-and-z408-on-grids.jpg Illustration showing how the 408 and 340 fit exactly on two sheets of 0.5" ruled grid paper]
* The 408's cipher alphabet is missing the cipher symbol C. The 340's cipher alphabet is missing the cipher symbol Q. It is strange that in both ciphers, Zodiac left out one letter from the cipher alphabet. He bothered to create new shapes and rotated letters, but still left out a "normal" letter in each cipher.
* Unverified: When the 340 and 408 ciphers are considered together, there is a total of 341 alphabetic symbols, and 407 non-alphabetic symbols. Both counts only differ by one with the respective cipher lengths. [http://www.zodiackillersite.com/viewtopic.php?p=43108#p43108 (Source: Marclean)]
* Z408 and Z340 each have an alphabet size that is divisible by 9: "9x7 = 63 Z340, 9x6 = 54 Z408. Just for inclusion 7 symbols were dropped from Z408 and 16 were added for a net gain of 9 in Z340." [http://www.zodiackillersite.com/viewtopic.php?p=48175#p48175 (Source: BartW)]
* When written vertically, some symbols repeat in a pattern similar to the period-19 reading order used to decrypt the Z340 ([http://www.zodiackillersite.com/viewtopic.php?p=85261#p85261 Source: Marclean])

= Z13 =
* Symbols on even positions do not repeat. Symbols on odd positions do (N and circled 8). [http://www.zodiackillersite.com/viewtopic.php?p=39032#p39032 (Source: daikon)]
* The cipher contains three symbols that look like circled 8's. Coincidentally, there are 8 "normal" symbols (excluding the upside down T). [https://www.facebook.com/groups/164298700375403/permalink/1508564075948852/ (Source: Ed Pittman)]
* There are 13 symbols, with A as the first and M as the last. This fits with the first half of the alphabet; there are 13 letters, A is the first, M is the last. AbcdefghijklM [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* The order of alphabet and non-alphabet characters is mirrored (or palindromic): (3-2-1-1-1-2-3): aen??k?m??nam [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* N is the third letter from the start and third from the end. [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)]
* It is possible to linearly sequence part of the alphabet mirrored around the central ciphered character: nmlklmn [http://zodiackillersite.com/viewtopic.php?f=81&t=5204 (Source: egg)] [https://i.imgur.com/T9GAfuL.jpg (Visualization)]
* Letters from the word "NAME" appear in the cipher text. The cleartext prior to the cipher says "My name is _____".
* The "circled 8" or "taurus" symbols are in symmetrical positions with respect to the center of the cipher text.
* "N" and "M" symbols appear in an orderly sequence: N, M, N and M. [http://zodiackillerciphers.com/images/z13-n-m-n-m.jpg (Illustration)]
* The "circled 8" or "taurus" symbols do not appear in Zodiac's other 3 ciphers. The upside down T also appears in Z32.
* The word "WANT" appears when the cipher is flipped vertically. [http://zodiackillerciphers.com/images/y3pM9.jpg (Illustration)]
* 3 symbols line up with a section of Z340. [https://web.archive.org/web/20170103143845/https://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (Source: traveller1st)] [http://www.zodiackillersite.com/viewtopic.php?p=1824#p1824 (original broken link)]
* The "E"s in the last 18 letters of Z408's plaintext line up with the 3 circled 8 symbols in Z13. [http://zodiackillerciphers.com/images/z13-vs-408-filler.jpg (Illustration)]
* The cipher text resembles Greek inscription "anetheke" which appears on ancient Greek temples and artifacts. [http://www.zodiackiller.com/MyNameIs.html (Source: Tom Voigt)] [http://www.zodiackillerciphers.com/?p=467 (More examples)]
* Decrypting the first 6 symbols of Z13 with Z408's and Z340's key produces plaintext letters that are clustered on a standard keyboard layout [http://www.zodiackillersite.com/viewtopic.php?p=83524#p83524 (Source: marclean)]
* If you skip 8 positions from each 8-ball symbol (including wrap around), it spells ME⌖ (Source: https://twitter.com/whatever23978)
* The "p.s." section in the bus bomb letter, when reversed, contains "AEN" and "NAM" which are also found in Z13. "K" and "M" also appear in the correct order (respective to Z13). [https://www.tapatalk.com/groups/zodiackillerfr/340-cipher-solution-t7316-s220.html#p198596 (source: rando, Shaqmeister)]
* The [https://zodiackillerfacts.com/gallery/thumbnails.php?album=16 October 5th 1970] card has 13 holes punched in it, reminiscent of the 13 symbols in Z13.

= Z13 and Z32 =
* Z13 begins with 3 symbols followed by a crosshairs symbol. Z32 ends with a crosshairs symbol followed by 3 symbols. (Source: Mike Cole) [http://zodiackillerciphers.com/images/z13-vs-z32-pattern.png (Illustration)]
* The line lengths of Z32 and Z13 are 17, 15, 13. (Source: Martin Jeppesen)

Exorcist letter markings

2023-12-09T21:47:59Z

Admin: /* Interpretations */

= The Letter =
* [https://www.zodiackiller.com/ExorcistLetter.html The Exorcist letter], mailed Jan. 29, 1974 to the SF Chronicle
** [https://zodiackiller.com/ELHR.html Higher resolution (color)]
** [https://zodiackiller.com/EEHR.html Envelope]
= Interpretations =
* [https://www.tapatalk.com/groups/zodiackillerfr/general-book-discussion-for-zodiac-killer-super-so-t10274.html#p203366 "Leigh" (animation)]
* [https://www.tapatalk.com/groups/zodiackillerfr/kim-allen-s-soy-sauce-barrel-t7517.html Kim Allen's soy sauce barrel]

Solution to the 340

2023-12-06T19:56:12Z

Admin: /* Thursday, December 3rd, 2020 */

== Raw text of the solution, after reversing transposition ==

''Presumed errors are in boldface:''

: I HOPE YOU ARE HAVING LOTS OF F'''A'''N IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRING'''O''' UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECA'''A'''SE IT WILL SEND ME TO PARAD'''L'''CE
: ALL THE SOO'''H'''ER BECAUSE '''E''' NOW HAVE ENOUGH SLAVES
: TO WOR'''V''' FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I '''V'''NOW THAT MY NEW
: LIFE IS LIFE WILL BE AN EASY ONE IN PARADICE DEATH

''With errors corrected:''

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE IS LIFE WILL BE AN EASY ONE IN PARADICE DEATH

== Interpretations of the seemingly misplaced words "LIFE IS" and "DEATH" ==

=== Group "LIFE IS" with "DEATH" ===

Example 1:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE WILL BE AN EASY ONE IN PARADICE.
: '''LIFE IS DEATH'''

Example 2:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE WILL BE AN EASY ONE IN PARADICE.
: '''DEATH IS LIFE'''

Example 3:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: '''LIFE IS DEATH'''. LIFE WILL BE AN EASY ONE
: IN PARADICE

Example 4:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH. '''LIFE IS DEATH'''. I AM NOT AFRAID
: BECAUSE I KNOW THAT MY NEW LIFE WILL BE AN EASY
: ONE IN PARADICE

Example 5:

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
: LIFE WILL BE AN EASY ONE: '''DEATH IS LIFE'''
: IN PARADICE.

''Additional speculation: The original ciphertext starts with the letters "HER", so perhaps the intended message formed from these fragments is "HER LIFE IS DEATH".''

=== Change "THAT" to "WHAT" ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW '''WHAT''' MY NEW
: LIFE IS: LIFE WILL BE AN EASY ONE IN PARADICE DEATH

=== "MY DEATH IS NEW LIFE" ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
: WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
: DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY
: '''DEATH IS NEW LIFE'''. LIFE WILL BE AN EASY ONE
: IN PARADICE

=== "WHERE DEATH IS LIFE" (suggested by Brandon Baskin) ===

: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO
: CATCH ME THAT WASNT ME ON THE TV SHOW WHICH
: BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE
: GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE
: ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES
: TO WORK FOR ME EVERYONE ELSE HAS NOTHING WHEN THEY
: REACH PARADICE SO THEY ARE AFRAID OF DEATH I AM
: NOT AFRAID BECAUSE I KNOW THAT MY NEW LIFE WILL
: BE AN EASY ONE IN PARADICE '''WHERE DEATH IS LIFE'''

== Verifications of the solution ==

* FBI confirmations:
** [https://twitter.com/FBISanFrancisco/status/1337477701825925120 FBI statement on their twitter account]
** [https://www.cnet.com/science/zodiac-killer-message-known-as-340-cipher-solved-after-51-years/ Article with excerpt from more detailed FBI statement]
** The full press release that was sent to me from the FBI press office:
*** ''The FBI has a team of cryptanalysis experts that decipher coded messages, symbols, and records from criminals known as the Cryptanalysis and Racketeering Records Unit. CRRU regularly works with the cryptologic research community to solve ciphers. On December 5, 2020, the FBI received the solution to a cipher popularly known as Z340 from a cryptologic researcher and independently verified the decryption. Cipher Z340 is one of four ciphers attributed to the Zodiac Killer. This cipher was first submitted to the FBI Laboratory on November 13, 1969, but not successfully decrypted. Over the past 51 years CRRU has reviewed numerous proposed solutions from the public–none of which had merit. The cipher was recently solved by a team of three private citizens. The Zodiac Killer case remains an ongoing investigation for the FBI San Francisco division and our local law enforcement partners. The Zodiac Killer terrorized multiple communities across Northern California and even though decades have gone by, we continue to seek justice for the victims of these brutal crimes. Due to the ongoing nature of the investigation, and out of respect for the victims and their families, we will not be providing further comment at this time.''
* [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/why-the-transposition-in-the-340-solution-is-inevitably-correct/#post-86366 f.reichmann's argument based on unicity distance]
*** [https://zodiackillerfacts.com/news-and-updates/breaking-news-the-zodiacs-340-cipher-has-been-solved/ Full FBI press release was included in Michael Butterfield's article]
* [https://www.youtube.com/watch?v=hIrOftXgibg Nils Kopal's verification]
* [https://eprint.iacr.org/2021/1620 ''Unicity distance of the Zodiac-340 cipher'' by Joachim von zur Gathen]

== More info ==

* [https://www.youtube.com/watch?v=-1oQLPRE21o Solution video 1]
* [https://www.youtube.com/watch?v=UfrFSrI05hk Solution video 2]
* [http://zodiackillerciphers.com/images/z340-key.png Image of the Z340 substitution key]
* [[Compilation of news reports about the solution]]
* [http://www.zodiackillerciphers.com/?p=869 Sam's slides] from his presentation, [https://www.youtube.com/watch?v=iuNyQ44JYxM "The Quest to Solve the Zodiac 340 Cipher"].
* [[Transposition matrices]]

== Timeline of arriving at the solution ==
''Times reported are in Eastern time in the USA''
=== Saturday, January 3, 2015 ===
* 05:56PM: [http://www.zodiackillersite.com/viewtopic.php?p=27087#p27087 Jarl's first post about availability of his new codebreaking software, AZdecrypt. (broken link)]
** [https://forum.zodiackillerciphers.com/community/zodiac-cipher-mailings-discussion/azdecrypt-beta-0-94/ Working link]

=== Tuesday, July 28, 2015 ===
* 01:02PM: Jarl posts his observations including period 19 bigram repeats [https://web.archive.org/web/20201212083301/http://www.zodiackillersite.com/viewtopic.php?f=81&t=2158&start=20 (original version in Wayback)] [https://zodiackiller.net/community/postid/39170/ (Live version)]
=== Wednesday, August 5, 2015 ===
* 12:45AM: Daikon posts his observations including period 19 bigram repeats [https://web.archive.org/web/20201212120731/http://www.zodiackillersite.com/viewtopic.php?p=39003 (original version in Wayback)] [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/things-i-noticed-about-z340/ Live version]
=== Wednesday, January 16, 2019 ===
* 09:12AM: Sam Blake's first contact with me, via comment on [https://www.youtube.com/watch?v=3Hk__Hk5c9M my 2018 ACA presentation video on Youtube.]
=== Thursday, August 1, 2019 ===
* 09:14PM: Sam Blake starts emailing me enumerations of Z340

=== Sunday, May 17th, 2020 ===
* 07:03AM: Jarl posts a [https://forum.zodiackillerciphers.com/community/zodiac-cipher-mailings-discussion/z340-multiple-transcription-rectangles/ transposition of the 340] which is extremely close to the correct final result.
** [http://zodiackillerciphers.com/jarl-transposition-3-sections-period-19.txt Transcription]
** [http://zodiackillerciphers.com/jarl-transposition-3-sections-period-19-pt.txt Plaintext resulting from applying final Z340 key to his transposed ciphertext]
** [https://zodiackiller.net/community/zodiac-cipher-mailings-discussion/z340-multiple-transcription-rectangles/ Old broken link]

=== Wednesday, December 2nd, 2020 ===
* 04:14PM: Began running 655,088 ciphers, the cumulative collection of all cipher enumerations and decimations Sam Blake has sent me to date, through AZDecrypt v1.19 with default settings (except for loading jarlve's reddit 6-grams). Had run many of them before, but this time I wanted to be more careful about sorting the results based on the cipher lengths (some manipulations remove parts of the cipher, which sometimes leads to azdecrypt reporting higher scores compared to ones for ciphers of length 340).
=== Thursday, December 3rd, 2020 ===
* 12:04PM: Reported an interesting result to Sam from one of his older vertical 3-split decimations
** [http://www.zodiackillerciphers.com/z340_vertical_3split_decimations_9_9_1_19_2.txt Transcription: z340_vertical_3split_decimations_9_9_1_19_2.txt]
*** [http://www.zodiackillerciphers.com/z340_vertical_3split_decimations_9_9_1_19_2_pt.txt Plaintext resulting from applying the final Z340 key to his transposed ciphertext]
** AZdecrypt generated this candidate plaintext:
*** EHOPE YOU ARE HE SING IST TORRA ENN
*** TRYING TO CATCH METH AFTAINT MT ON THE
*** TS SHOT WHICH BRINGS UP ALS IN TABS IT
*** ME NAME OF AR HEED OR THE GAS CHAMBER
*** BECA ATE IT WILD VENT ME ROLER A DICE
*** AI I THE VS SHEN BECAUSE TOO WHA SEEN
*** TIGHT DESERTS WORS ROS ME THERE
*** EVERYONEED HE HAS NOTHING THEN THEY HE
*** ACH PARADICT IS THEY ALREARE AND NORDER
*** THER AMEO EARRE AND BECAUITE IS YOT TV
*** HAT MR NEWE ITLE NEVER IND BAEYN NEIA
*** AT A HOE CDR PET
** A few interesting legible phrases stood out right away:
*** HOPE YOU ARE
*** TRYING TO CATCH ME
*** SHOT WHICH BRINGS UP
*** OR THE GAS CHAMBER
*** HE HAS NOTHING THEN THEY
** Phrases were more noticeable due to the auto-whitespace feature Jarl added for v1.19.
* 03:25PM: Determined the transposition (decimation) steps that were performed for that cipher among Sam's batch.
* 07:50PM: Sam provides details on the 9,9,1,19,2 enumeration, which is actually split into 4 vertical groups of size 9, 9, 1, and 1. A decimation of 19,2 is applied to each group.
* 09:36PM: I reported to Sam my solution to the first 9 lines, obtained by isolating those 9 lines, feeding them into AZdecrypt, but locking in cribs for some of the interesting phrases discovered earlier.
** The plaintext read: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO CATCH ME THAT WASNT ME ON THE TV SHOW WHICH BRING OR PA POINT ABOUT ME I UM NOT A FRA IF OF THE GAS CHAMBER BECUASE IT WILL SEND ME TO PAY UNLCE ALL THE
** The first section contains every symbol used in the entire cipher, so applying the key to the entire cipher text gave this plaintext: I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO CATCH ME THAT WASNT ME ON THE TV SHOW WHICH BRING OR PA POINT ABOUT ME I UM NOT AFRAID OF THE GAS CHAMBER BECUASE IT WILL SEND ME TO PAY UNLCE ALL THE SOO HEN BE CURSEE OOW HAVE ENSUGH SLAVER TO WOR V FOV ME WHERE ESERYONE EL HEH US NOTHING WHEN THEY REACH PAY UNICE SO TREY ALREU FAA I FI OF NET TH IF AM NO EA FREA IF BNC ARISE IV YO WT SHAT MR NEW EIW LENESE FLIL BAAYNNE I UADAHO I CFR PET
** Appearance of phrase "THAT WASNT ME ON THE TV SHOW" locked this in as a solid lead towards a real solution. Second 9 lines yielded from the same key have a relatively high score (compared to random plaintext or gibberish) but is somewhat garbled. Also noticed the word DEATH appearing at the very end of the last line of the entire cipher, using same key as the one discovered for the first 9 lines. Asked Sam for help to figure out the remaining 11 lines.
* 10:04PM: Notified Jarl to also ask for his help.

=== Friday, December 4rd, 2020 ===
* 08:04AM: Ran several other decimations from Sam to try to isolate other schemes that might lead to a solve for the remaining 11 lines.
* 09:29AM: Completed a search of over 400,000 AZdecrypt results and determined that the phrase GAS CHAMBER appears in no other result.
* 10:10AM: Ran some more decimations from Sam. Didn't notice anything substantial in the results.
* 11:19AM: First response from Jarl, "It looks genuine!"
* 02:17PM: I report reversed words in the last 2 lines to Sam and Jarl
* 02:23PM: Jarl independently reports reversed words in the last 2 lines.
* 02:31PM: I interpreted the garbled 2nd section to read like this:
** BECAUSE ? SLAVES TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF LETTING ?? BECAUSE I (VOW?)...
* 02:40PM: Refined 2nd section:
** BECAUSE ??? HAVE ENOUGH SLAVES TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF LETTING ?? BECAUSE I (VOW?)...
* 02:58PM: Jarl reports his refined solution:
**I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING
**TO CATCH ME THAT WASNT ME ON THE TV SHOW
**WHICH BRINGS UP A POINT ABOUT ME I AM NOT
**AFRAID OF THE GAS CHAMBER BECAUSE IT WILL
**SEND ME TO PARADICE ALL THE
**
**SOO HEN BECAUSE EOOW HAVE ENOUGH SLAVES TO
**WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
**WHEN THEY REACH PARADICE SO THEY ALRE UFA AID
**I OF DET TH IF AM NO EA FREA ID BN CA AISE IV
**YO WT SHAT MR NEW
**
**EFIL WILL EB NA EASY E
**NONI ECIDARAP DEATH
* 03:18PM: I report my finding about the errors on line 15 (the 6th line of the 2nd section). Several errors are happening on the same line, suggestive of a systematic mistake.
* 03:23PM: Jarl reports his interpretation of the plaintext:
** SO THEY'RE ALL AFRAID OF DEATH I AM NOT AFRAID BECAUSE IT ...
* 04:19PM: I'm considering sending our partial solve to the FBI so they can help us work out the rest of it
* 05:47PM: Decided against reporting the solve early, to give our team more time to work it out. Developed a visualization of the errors on line 15 (6th line of the 2nd section).

=== Saturday, December 5th, 2020 ===
* 01:26AM: Jarl reports progress on the plaintext, resulting from a possible "skip" in the 2nd part. Jarl's latest plaintext:
** I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING
** TO CATCH ME THAT WASNT ME ON THE TV SHOW
** WHICH BRINGS UP A POINT ABOUT ME I AM NOT
** AFRAID OF THE GAS CHAMBER BECAUSE IT WILL
** SEND ME TO PARADICE (ALL THE)
**
** (SOO HEN) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO (THEYRE ALL) AFRAID
** OF DEATH I AM NOT AFRAID BECAUSE IT
** (YO WT SHAT MR NEW)
**
** EFIL WILL EB NA EASY ENO
** NI ECIDARAP DEATH
* 02:16AM: Jarl reports more detail on the skip in the 15th row, and the skip seems isolated to that row. But still some garble happening after that is fixed.
* 02:41AM: Jarl reports discovery that skipping cleartext "LIFEIS" in upper right section of the 2nd block fixes the remaining garbles. Plaintext now only has a few errors remaining.
* 02:50AM: Jarl reports full plaintext:
** I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING
** TO CATCH ME THAT WASNT ME ON THE TV SHOW
** WHICH BRINGS UP A POINT ABOUT ME I AM NOT
** AFRAID OF THE GAS CHAMBER BECAUSE IT WILL
** SEND ME TO PARADICE (ALL THE)
**
** (SOO HER) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO THEY ARE AFRAID
** OF DEATH I AM NOT AFRAID BECAUSE I KNOW THAT
** MY NEW LIFE IS
**
** EFIL WILL EB NA EASY ENO
** NI ECIDARAP DEATH
* 03:44AM: Jarl reports details on steps that were required to fix the 2nd section:
** Right-offset the RATENYRNOSRVSH fragment by 1 becoming HRATENYRNOSRVS. I think he skipped the H by mistake (during homophonic step) and then realized his error going into the 7th row and added the H back in at the end of the 6th row.
** Skip the positions of the "LIFEIS" fragment during untransposition.
** Now after transposition it will result in:
**
** (SOO HER) BECUASE E NOW HAVE ENOUGH SLAVES TO
** WORV FOR ME WHERE EVERYONE ELSE HUS NOTHING
** WHEN THEY REACH PARUDICE SO THEY ARE UFRAID OF
** DEATH I AM NOT AFRAID BECAASE I VNOW THAT MY NEW
**
** Fixing a few errors:
**
** (SOO HER) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
** DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW
**
** Since the "LIFEIS" fragment was skipped it can be added in somewhere else, and I think it has to be at the end:
**
** (SOO HER) BECAUSE I NOW HAVE ENOUGH SLAVES TO
** WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING
** WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF
** DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW (LIFE IS)
* 07:56AM: I completed a PDF report of our solution and submitted it to my contacts at the FBI crypto lab.
* 08:02AM: First response from FBI crypto lab, unofficial confirmation
* 08:48AM: Second response, unofficial confirmation
* 08:49AM: Third response, further confirmation, phone call
Not sure about further timing on this day, but during the day the FBI took action on the solution, notifying others in the agency as well as working on a report of the solution to submit back to SFPD, the original requestor. Submission also planned to SF FBI.
=== Sunday, December 6th, 2020 ===
CRRU submitted the solution to FBI San Francisco in the evening.
Waiting for contact with FBI National Press Office to coordinate release of this news.

=== Monday, December 7th, 2020 ===
Talked to FBI National Press Office in the afternoon to discuss release plan. Allowing for all victim notifications to take place prior to releasing the news.
=== Thursday, December 10th 2020 ===
Talked to FBI National Press Office in the afternoon and was informed that final notifications will be completed by the end of the day and that the best time for the news release will be Friday.

[https://www.tapatalk.com/groups/zodiackillerfr/viewtopic.php?p=159817#p159817 Teased the pending release of the news.]

=== Friday, December 11th 2020 ===
* 06:00AM: [https://youtu.be/-1oQLPRE21o Explainer video (Let's Crack Zodiac Episode 5)] switched to Public. I posted the news on many social media outlets and forums, and emailed the LCZ mailing list.
** Post on [https://www.tapatalk.com/groups/zodiackillerfr/the-340-cipher-has-been-solved-t9434.html#p159875 Tom Voigt's forum]
** Post on [https://zodiackiller.net/community/news-wire/z340-has-been-solved/ Mike Morford's forum]
* 01:03PM: First news report by SF Chronicle, [https://twitter.com/KevinChron/status/1337458070570508289 announced by long time Zodiac reporter Kevin Fagan]
* 02:21PM: FBI San Francisco makes a public announcement of the solution [https://twitter.com/FBISanFrancisco/status/1337477701825925120 on their twitter account.]

Over the next several days, many news outlets reported on the solution.
[http://zodiackillerciphers.com/wiki/index.php?title=Compilation_of_news_reports_about_the_solution Click here for a compilation.]