PlaySudoku.us
Easy · Puzzle #530
3
8
7
1
8
7
9
6
2
9
5
7
4
8
9
7
5
4
8
1
3
7
3
4
8
3
8
1
2
6
7
6
9
2
1
8
9
6
3
4
1
3
4
2
6
9
7
"Mathematicians do not study objects, but relations between objects." — Henri Poincaré
"Mathematicians do not study objects, but relations between objects." — Henri Poincaré
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.