On the Subject of the Arithmetic Sequence CM
A machine that knows no bounds when it comes to ciphers.
From the ƎNA Cipher module by Kilo Bites.
Create a key using the keyword on screen 1 and the Boolean Expression on screen A. This will be referred to as the Sequence Key.
If there is a number on screen B, take out the letter at that position in the encrypted word. Set aside this letter to be put back in at a later step.
Split the encrypted word into letter pairs and for each pair, do the following:
- Note the movement from the 1st letter in the pair to the 2nd letter in the pair within the Sequence Key. (You can pick either direction.)
- Repeat the movement from the 2nd letter to obtain a letter.
- Then repeat the same movement again from the letter you obtained in the last step.
- Reverse the order of the letter pair you got from the previous steps to get a decrypted letter pair.
After doing the sequence for each pair of encrypted letters, if you took out a letter, insert that letter back into position equal to the number on screen B. You should now have a decrypted word.
Example
Encrypted Word: ASSHFSB
Sequence Key: YACHTSBDEFGIJKLMNOPQRUVWXZ
Screen B: 1
ASSHFSB + 1 → SSHFSB
SS → SS → SS
FH → MU → UM
SB → DE → ED
SSUMED + A + 1 → ASSUMED
Decrypted Word: ASSUMED