PlaySudoku.us
Easy · Puzzle #226
5
9
3
8
7
9
3
8
2
5
3
8
6
2
7
4
1
5
8
1
9
7
6
9
4
8
5
8
5
3
4
4
3
6
9
2
5
9
3
2
4
1
6
8
5
7
Set theory provides the formal foundation for Sudoku's rules: each digit must appear exactly once per set.
Set theory provides the formal foundation for Sudoku's rules: each digit must appear exactly once per set.
"As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality." — Albert Einstein
"As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality." — Albert Einstein