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OT: The Fifteen Puzzle book



#2

I recently purchased a book on the history of the Fifteen puzzle. If you remember, this is a sliding piece puzzle with counters for the numbers 1-15 and an empty cell for moving the pieces around, the goal being to get them in sequence. It's a great puzzle, and the book is excellent. It is magnificently illustrated and researched, and it proves that the supposed "inventor" of the puzzle, Sam Loyd, was actually not the inventor. It also includes a mathematical description of why certain configurations of the puzzle are not solvable. Fascinating.

Here is the link.


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