Did You Know?

Sudoku has no math — you could replace the digits 1–9 with any 9 symbols and the puzzle works identically.

Did You Know?
✓ Completed! 👍
6
3
4
2
8
1
7
8
4
6
2
3
1
9
2
3
6
4
8
7
8
9
5
5
4
9
1
7
9
1
8
7
2
4
6
5
3
8
1
4
8
5
2
7
3
7
3
9
Did You Know?

Sudoku is listed as a recommended mental exercise in several cognitive rehabilitation programs for TBI (traumatic brain injury) patients.

Did You Know?