2
3
8
1
6
4
5
4
1
3
3
9
5
6
8
9
6
2
4
3
3
5
4
1
2
1
4
4
9
5
2
3
7
4
9
8
2
The minimum number of clues needed to create a valid Sudoku with a unique solution is 17.
The minimum number of clues needed to create a valid Sudoku with a unique solution is 17.
The minimum number of clues needed to create a valid Sudoku with a unique solution is 17.
The minimum number of clues needed to create a valid Sudoku with a unique solution is 17.