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StringMash Daily #7

Friday 9 October 2026 · Hard · Affine cipher. Any day's puzzle can be played, and counts as solved.

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    About puzzle #7

    Puzzle #7 is the one for Friday 9 October 2026: a hard Friday puzzle, in Affine cipher. Each letter number x becomes (a × x + b) mod 26. With a and b known, the step can be undone with the inverse of a.

    Stuck? The Affine cipher decoder is fair to use, and Hint fills in one letter at a time. A new puzzle opens every day at midnight where you are, at StringMash Daily, and every earlier one is in the archive under the puzzle.