Notice of corrupted results: Vigenere may yet be found to be a "group."

Retraction:


It is with regret that I do not delete the previous post. I am an individual, not an organization, and I failed to adequately double-check my results, but I am leaving the post to maintain some accountability.

I am able to definitively say that the script for 2chars_from_file.py DOES NOT yield an exhaustive list. It develops the ciphertext for all 2 Char combinations of the FIRST 10, three character ciphertexts.

This is not due to a logic error, but rather there is a virus that corrupts the indentation of the two write statements. 

This may be verified by downloading the relevant code, and examining it, and running it if needed, against the relevant datafile. It is difficult to be exhaustively correct about ALL of the scripts.

This calls ALL of my results in question, with regard to the qualification of a mathematical group.

If Vigenere IS a group, the resulting substitution is still valid, but there exist 6 Char passwords that will accomplish the same encryption in ONE STEP. 2*(10^2)*(10^3) is < 10^6, so there are fewer possible messages from this improved periodicity, but searching "6 space," is more difficult than brute force.

A six character password in very practical, but multiple "rounds" of Vigenere may still extend the period usefully beyond what is practical for a single password.

I am extremely disappointed, and I cannot satisfy myself about the answers until I re-install my OS and re-develop the code from memory without the virus.

VIGENERE MAY YET BE FOUND TO BE A "GROUP." However, we CAN be satisfied that col, row lookup is NOT a hash.

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