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arXiv · 2310.15279

The linear system for Sudoku and a fractional completion threshold

Peter J. Dukes·Kate Nimegeers
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Abstract

We study a system of linear equations associated with Sudoku latin squares. The coefficient matrix $M$ of the normal system has various symmetries arising from Sudoku. From this, we find the eigenvalues and eigenvectors of $M$, and compute a generalized inverse. Then, using linear perturbation methods, we obtain a fractional completion guarantee for sufficiently large and sparse rectangular-box Sudoku puzzles.

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Peter J. Dukes, Kate Nimegeers. 2024-04-16. The linear system for Sudoku and a fractional completion threshold. https://arxiv.org/abs/2310.15279

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