2021-11-09 19:45:01 +00:00
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= Affine =
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Affine cipher is a type of [[substitution]] cipher.
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The cipher is of model
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f(x) = ax + b mod 26
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Where x is some number corresponding to a letter, 0-25. a and b are variables.
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To decipher, the formula is of form
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f(y) = a^-1(y - b) mod 26
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Where y is the ciphertext value, and a^-1 is the modular multiplicative inverse
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of a
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