Disconnected Cliques in Derangement Graphs
<|reference_start|>Disconnected Cliques in Derangement Graphs: We obtain a correspondence between pairs of $N\times N$ orthogonal Latin squares and pairs of disconnected maximal cliques in the derangement graph with $N$ symbols. Motivated by methods in spectral clustering, we also obtain modular conditions on fixed point counts of certain permutation sums for the existence of collections of mutually disconnected maximal cliques. We use these modular obstructions to analyze the structure of maximal cliques in $X_N$ for small values of $N$. We culminate in a short, elementary proof of the nonexistence of a solution to Euler's $36$ Officer Problem.<|reference_end|>
@article{anderson2024disconnected,
    title={Disconnected Cliques in Derangement Graphs},
    author={Sara Anderson, W. Riley Casper, Sam Fleyshman, and Matt Rathbun},
    journal={arXiv preprint arXiv:2407.14155},
    year={2024},
    archivePrefix={arXiv},
    eprint={2407.14155},
    primaryClass={math.CO cs.DM math.RT}
}