Did You Know?

Finnish mathematician Arto Inkala created what is widely considered the world's hardest Sudoku in 2012.

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

Finnish mathematician Arto Inkala created what is widely considered the world's hardest Sudoku in 2012.

Did You Know?