PlaySudoku.us
Expert · Puzzle #800
3
1
5
7
2
6
6
1
5
7
4
4
6
5
8
2
3
5
8
6
1
9
4
8
7
3
The pigeonhole principle explains why 8 clues are never enough to guarantee a unique Sudoku solution.
The pigeonhole principle explains why 8 clues are never enough to guarantee a unique Sudoku solution.
The maximum number of givens in a Sudoku that still leaves the rest logically deducible (no trivial completion) can exceed 77.
The maximum number of givens in a Sudoku that still leaves the rest logically deducible (no trivial completion) can exceed 77.