According to Wolfram Alpha, the Ostomachion is a 14-piece dissection puzzle described in fragmentary manuscripts attributed to Archimedes as noted by Magnus Ausonius (310-395 A.D.). This makes it one of the oldest known puzzles.

In November 2003, Bill Cutler found there to be 536 possible distinct arrangements of the pieces into a square, illustrated above, where solutions that are equivalent by rotation and reflection are considered identical (Pegg 2003). Despite this, finding just one arrangement is incredibly challenging!

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