Yes, so all of us who gave up on cipher number 3 can relax now!

The Cipher Challenge was published in The Code Book by Simon Singh over a year ago. It consisted of ten encrypted messages, which started out with a very easy cipher and ended in "the toughest public challenge cipher yet devised", being a RSA-encrypted message with a 155 digit key

The challenge was officially solved on October 7, 2000 by a Swedish team consisting of four people. The tenth cipher required 67 years computational run-time to solve. The winning team will now share the £10,000 awarded by Singh. Another £1,000 were awarded to the leaders on October 1, 2000, which was a little over one year after the challenge was proclaimed. That money went to another team that has managed to solve the ninth cipher by that time. This group had the solution to all ciphers but the fifth and the tenth by October 8, 1999

Except for the tenth stage, it turned out that the fifth cipher was the trickiest. Being a Beale-type cipher, a.k.a. book cipher, it required a key text in order to solve, and there was simply no clue whatsoever as to what text that might be. Most teams solved the ciphers up to eight or nine before number five. It turned out to be the famous Fermat's Last Theorem - in Latin ! Well, that wasn't completely taken out of nowhere, but anyway. The winning team used programs that retrieved hundreds of texts from The Gutenberg Project and tried them, to no avail.

Simon Singh himself was surprised that the last cipher was solved so rapidly; he had anticipated another 5 years or so before anyone managed it.

Read sloutions and more at http://simonsingh.com/cipher.htm

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