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Sudoku Links

Puzzles we like Nikoli, home of the best Japanese pencil puzzles, such as Masyu, Fillomino, and Yajilin. Logic Games Online, who publishes the excellent Japanese pencil puzzle Nurikabe, as well as Sudoku and other puzzles. janko.at, a stunning array of online puzzles, including many of our favorite Japanese pencil puzzles. Sudoku Odyssey: Suki and the Beasts, a beautiful journey through Sudoku puzzle mazes. Sudoku Games Collection, a large online collection of Sudoku puzzles and variants. Sudoku Evolution, with some of the most creative geometric variations of Sudoku we've seen. Math Games: Sudoku Variations by Ed Pegg, an excellent article full of Sudoku variations found in Japanese puzzle magazines.

Sudoku research and articles Mathematics of Sudoku entry at Wikipedia. Taking Sudoku Seriously, an article by Laura Taalman in Math Horizons. Puzzling over Sudoku, an article by Laura Taalman in Madison Magazine. Minimum Sudoku, a collection of over 40,000 17-clue puzzles by Gordon Royle. Mathematics of Sudoku I (enumerating Sudoku grids), by Felgenhauer and Jarvis. Mathematics of Sudoku II (enumerating essentially different Sudoku grids), by Russell and Jarvis. Sudoku, gerechte designs, resolutions, affine space, spreads, reguli, and Hamming codes, by Biley, Cameron, and Connelly. Mathematics of Sudoku, Roku Doku, and Shidoku, by Sourendu Gupta. An Integer Programming Model for the Sudoku Problem, by Bartlett, Chartier, Langville, and Rankin, Journal of Online Mathematics. Sudoku as a Constraint Problem, by Helmut Simonis. Sudokus and Gröbner Bases: Not Only a Divertimento, by Gago-Vargas, Hartillo-Hermoso, Martín-Morales, and Ucha-Enríquez. UC Irvine Sudoku Research by computer science professor David Eppstein, who investigates nonrepetitive paths and cycles in graphs. Partial Chromatic Polynomials and Diagonally Distinct Sudoku Squares, by Füsun Akman. Graph Algorithms article from Dr. Dobb's Portal on using graph theory to build Sudoku solvers. Forbidding Chains as a generalization of all Sudoku solving strategies. Sudoku Squares and Chromatic Polynomials, by Agnes Hertzberg and Ram Murty, from the AMS Notices. Benjamin Franklin Plays Sudoku, by Julie J. Rehmeyer, at Science News Online.

Sudoku Solvers Sudoku Solver By Logic is valuable for showing exactly how it solved a puzzle. Andrew Stuart's Sudoku Solver uses a huge number of advanced techniques.