Minimum amount of clues for a 16x16 sudoku

I know that 17 is the minimum for a standard 9x9 (3x3 squares), but what about a 16x16 (4x4 squares) sudoku?

• When you say 3x3 and 4x4, do you mean 9x9 (standard) and 16x16 (what's in the title)? – Rand al'Thor Sep 12 '19 at 16:32
• Of possible interest is Wikipedia's "Mathematics of Sudoku" section Sudokus of other sizes. – Weather Vane Sep 12 '19 at 19:50
• The answer is here: forum.enjoysudoku.com/… – Duck Sep 12 '19 at 22:14

1 Answer

As the comments say, the smallest number of clues found for a 16x16 sudoku (with 4x4 squares) is 55. It has not been proven that this is the smallest number, but no one's found a better one yet. I suspect that less research into a minimum number has occurred for the larger variants because they are less common and would require more computing power to brute-force.

References:

Wikipedia

16×16(4×4) Sudoku: At least one puzzle with 55 clues has been created. It is not known if this is the fewest possible.

The example 55-clue Sudoku