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Math Games: Sudoku Variations - http://www.maa.org/editorial/mathgames/mathgames_09_05_05.html
Offers detailed descriptions and illustrations of Sudoku variations, including Diagonal, Cubical, Even-Odd, and hybrids. Also includes a short history. |
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Sudoku-Ball - http://www.sudoku-ball.com/
A three dimensional version of the puzzle. Includes game rules, online version and news. |
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Mathematical Recreations - http://www.mathrec.org/sudoku/
Custom Word Doku puzzles devised by Steve Schaefer. Features an entire sentence embedded into the puzzle. |
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Sudokuto - http://www.menneske.no/sudokuto/eng/
Two-player variant. Offers several board sizes to play against the computer. [English/Norsk] |
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Sudoku Samurai - http://www.binaryworlds.com/sudoku/
Offers printable sudoku samurai puzzles for download. |