PlaySudoku.us
Hard · Puzzle #563
2
3
7
1
4
6
2
9
1
5
7
9
7
8
9
4
3
3
4
7
9
6
7
4
5
9
6
2
"The only impossible journey is the one you never begin." — Tony Robbins
"The only impossible journey is the one you never begin." — Tony Robbins
The number of essentially different Sudoku grids (accounting for symmetry) is 5,472,730,538 — about 5.5 billion.
The number of essentially different Sudoku grids (accounting for symmetry) is 5,472,730,538 — about 5.5 billion.