Regardless of the math behind them, you’ll find they call these evil sudoku puzzles because they are hard to solve. This is a link to his minimum sudoku page, but I also highly recommend the article he wrote here on sudoku complexity for those interested in some of the math, especially a more readable discussion of Gary McGuire’s research on the topic. Gordon Royle at the University of Western Australia maintains a repository of N-17 sudoku, and the evil sudoku puzzles in this section are derived from the patterns he provides on his site. SUDOKU EVIL Volume 1: Sudoku Evil: Very Hard (400 diabolical puzzles, difficult level for extreme sudoku puzzle enthusiasts) Ardson, A.

There are still a quite large number of possible puzzles (most variations of equivalent puzzles of the same form) that can be created. Evil Sudoku Puzzles are made for those players who are extremely confident in their logic skills and believe to be experts by now. Because a valid sudoku puzzle must have exactly one unique. Sudoku masters have known for some time that the absolute minimum number of clues a puzzle can have and still be valid is 17. Evil Sudoku includes some of the most challenging Sudoku puzzles that are mathematically possible. But as the number of sudoku clues decreases, these contraints make other solutions much more likely. This is pretty easy if the sudoku has lots of clues because it winds up requiring very specific values in very specific spaces of the solution.

Each puzzle must meet the constraints required to solve it, but additionally it must be constrained enough to require a unique and specific solution. Because a valid sudoku puzzle must have exactly one unique solution, coming up with a sudoku puzzle can often be more challenging than solving one. Evil Sudoku includes some of the most challenging Sudoku puzzles that are mathematically possible.

Sudoku evil