PlaySudoku.us
Expert · Puzzle #597
9
3
2
4
3
1
6
9
2
4
1
5
4
8
9
5
1
6
2
8
3
5
6
"A theory that is not refutable by any conceivable event is non-scientific." — Karl Popper
"A theory that is not refutable by any conceivable event is non-scientific." — Karl Popper
There are Sudoku variants with extra constraints: Killer Sudoku (cage sums), Diagonal Sudoku, and even 3D Sudoku.
There are Sudoku variants with extra constraints: Killer Sudoku (cage sums), Diagonal Sudoku, and even 3D Sudoku.