Follow Slashdot blog updates by subscribing to our blog RSS feed


Forgot your password?
Slashdot Deals: Cyber Monday Sale! Courses ranging from coding to project management - all eLearning deals 25% off with coupon code "CYBERMONDAY25". ×

Submission + - Minimum number of clues required to crack Sudoku f (

ananyo writes: An Irish mathematician has used a complex algorithm and millions of hours of supercomputing time to solve an important open problem in the mathematics of Sudoku, the game popularized in Japan that involves filling in a 9X9 grid of squares with the numbers 1–9 according to certain rules.

Gary McGuire of University College Dublin shows in a proof posted online that the minimum number of clues — or starting digits — needed to complete a puzzle is 17; puzzles with 16 or fewer clues do not have a unique solution. Most newspaper puzzles have around 25 clues, with the difficulty of the puzzle decreasing as more clues are given.

This discussion was created for logged-in users only, but now has been archived. No new comments can be posted.

Minimum number of clues required to crack Sudoku f

Comments Filter:

Programmers used to batch environments may find it hard to live without giant listings; we would find it hard to use them. -- D.M. Ritchie