Sudoku puzzles disjoint groups(Su Doku)My database includes 2383 puzzles for the moment and I'm constantly generating more.
Rules: Fill in the grid so that every row, every column, and every 2x2 box contains the digits 1 through 4. The cells with the same color must also contain the digits 1 through 4. There is only 1 solution for each puzzle.
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153277 puzzles downloaded.