PlaySudoku.us
Expert · Puzzle #978
8
1
7
8
2
6
7
5
2
4
6
9
7
8
3
2
3
9
4
3
8
9
5
1
"We suffer more often in imagination than in reality." — Seneca
"We suffer more often in imagination than in reality." — Seneca
In combinatorics, the pattern formed by Sudoku clue cells is studied as a problem in 'hitting sets' and transversals.
In combinatorics, the pattern formed by Sudoku clue cells is studied as a problem in 'hitting sets' and transversals.