Mirrored from Sudopedia, the Free Sudoku Reference Guide
Two Sudoku puzzles are mathematically equivalent if one can transform the first into the second via a series of zero or more operations, where the allowed operations are:
If a puzzle P can be solved using a set of solving techniques, then any puzzle that is mathematically equivalent to P can also be solved using the same set of solving techniques. However, Sudoku Programs may rate two mathematically equivalent puzzles slightly differently because a different solving path is used. When a program checks for patterns one digit at a time, relabeling the digits may cause the solver to find patterns of similar nature in a different order.