In Number Theory, Logic, and Cryptography

Zodiac 340 Cipher


The Zodiac killer was responsible for several murders (the exact number is disputed) in the San Francisco area in the late 1960s, and possibly also the early 1970s.  He sent several letters and ciphers to newspapers during this time.  His first cipher was solved.  His second, reproduced here, and sometimes known as the 340 cipher, remains unsolved to this day: his identity is still unknown.

























The problem is to solve the cipher.

The Zodiac Cipher has now been solved. See item 1 in the References below for details.


For further information, please see:

[1] https://www.abc.net.au/news/2020-12-12/zodiac-killer-code-cracked-by-australian-mathematician/12977342/

[2] http://en.wikipedia.org/wiki/Zodiac_Killer

[3] http://www.zodiackiller.com/Letters.html

[4] http://zodiackillerciphers.com/wiki/index.php?title=Encyclopedia_of_observations



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