Robuta

https://arxiv.org/abs/1201.0749v1 [1201.0749v1] There is no 16-Clue Sudoku: Solving the Sudoku Minimum Number of Clues Problem Abstract page for arXiv paper 1201.0749v1: There is no 16-Clue Sudoku: Solving the Sudoku Minimum Number of Clues Problem