English

How to burn a Latin square

Combinatorics 2024-07-31 v1

Abstract

We investigate the lazy burning process for Latin squares by studying their associated hypergraphs. In lazy burning, a set of vertices in a hypergraph is initially burned, and that burning spreads to neighboring vertices over time via a specified propagation rule. The lazy burning number is the minimum number of initially burned vertices that eventually burns all vertices. The hypergraphs associated with Latin squares include the nn-uniform hypergraph, whose vertices and hyperedges correspond to the entries and lines (that is, sets of rows, columns, or symbols) of the Latin square, respectively, and the 33-uniform hypergraph, which has vertices corresponding to the lines of the Latin square and hyperedges induced by its entries. Using sequences of vertices that together form a vertex cover, we show that for a Latin square of order nn, the lazy burning number of its nn-uniform hypergraph is bounded below by n23n+3n^2-3n+3 and above by n23n+2+log2n.n^2-3n+2 + \lfloor \log_2 n \rfloor. These bounds are shown to be tight using cyclic Latin squares and powers of intercalates. For the 33-uniform hypergraph case, we show that the lazy burning number of Latin squares is one plus its shortest connected chain of subsquares. We determine the lazy burning number of Latin square hypergraphs derived from finitely generated groups. We finish with open problems.

Cite

@article{arxiv.2407.20370,
  title  = {How to burn a Latin square},
  author = {Anthony Bonato and Caleb Jones and Trent G. Marbach and Teddy Mishura},
  journal= {arXiv preprint arXiv:2407.20370},
  year   = {2024}
}
R2 v1 2026-06-28T17:57:29.823Z