11
$\begingroup$

In a sudoku puzzle, what is the absolute minimum number of clues that must be given to specify a layout with a unique solution? Is one in each row, column, and box (9 total) necessary or sufficient?

$\endgroup$
17
$\begingroup$

For a standard $9 \times 9$ sudoku, the minimum is $17$ squares. It had long been known that at least $16$ were required and that $17$ was sufficient. This article closes the gap.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.