Bounding the number of arithmetical structures on graphs
arXiv:2007.15100 · doi:10.1016/j.disc.2021.112494
Abstract
Let be a connected undirected graph on vertices with no loops but possibly multiedges. Given an arithmetical structure on , we describe a construction which associates to it a graph on vertices and an arithmetical structure on . By iterating this construction, we derive an upper bound for the number of arithmetical structures on depending only on the number of vertices and edges of . In the specific case of complete graphs, possibly with multiple edges, we refine and compare our upper bounds to those arising from counting unit fraction representations.
11 pages