Abstract
We introduce a graph attached to mutually orthogonal Sudoku Latin squares. The spectra of the graphs obtained from finite fields are explicitly determined. As a corollary, we then use the eigenvalues to distinguish non-isomorphic Sudoku Latin squares.
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Acknowledgements
The authors would like to thank the referees for their careful reading and valuable comments. Sho Kubota is supported by JSPS KAKENHI Grant Number 20J01175, and Sho Suda is supported by JSPS KAKENHI Grant Number 18K03395 and 22K03410.
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JSPS 20J01175, 18K03395.
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Kubota, S., Suda, S. & Urano, A. Mutually Orthogonal Sudoku Latin Squares and Their Graphs. Graphs and Combinatorics 39, 122 (2023). https://doi.org/10.1007/s00373-023-02718-9
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DOI: https://doi.org/10.1007/s00373-023-02718-9