1
5
4
7
8
5
6
6
2
8
5
4
8
1
7
7
3
6
8
5
9
5
6
1
8
6
1
2
7
8
7
8
9
6
3
1
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.