# There Is No 16-Clue Sudoku: Solving the Sudoku Minimum Number of Clues Problem via Hitting Set Enumeration

```@article{McGuire2014ThereIN,
title={There Is No 16-Clue Sudoku: Solving the Sudoku Minimum Number of Clues Problem via Hitting Set Enumeration},
author={Gary McGuire and Bastian Tugemann and Gilles Civario},
journal={Experimental Mathematics},
year={2014},
volume={23},
pages={190 - 217}
}```
• Published 1 January 2012
• Computer Science
• Experimental Mathematics
The sudoku minimum number of clues problem is the following question: what is the smallest number of clues that a sudoku puzzle can have? For several years it had been conjectured that the answer is 17. We have performed an exhaustive computer search for 16-clue sudoku puzzles and did not find any, thus proving that the answer is indeed 17. In this article we describe our method and the actual search. As a part of this project, we developed a novel way to enumerate hitting sets. The hitting set…
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