Sharp estimates for spanning trees
Combinatorics
2022-04-14 v4
Abstract
We prove the following sharp estimate for the number of spanning trees of a graph in terms of its vertex-degrees: a simple graph on vertices has at most spanning trees. This result is tight (for complete graphs), and improves earlier estimates of Alon from 1990 and Kostochka from 1995 by a factor of about (for dense graphs). We additionally show that an analogous bound holds for the weighted spanning tree enumerator of a (nonnegatively) weighted graph as well.
Keywords
Cite
@article{arxiv.2102.01669,
title = {Sharp estimates for spanning trees},
author = {Steven Klee and Bhargav Narayanan and Lisa Sauermann},
journal= {arXiv preprint arXiv:2102.01669},
year = {2022}
}
Comments
It has been pointed out to us when this paper was under review that the results are not new; in fact a stronger bound was proved by Grone and Merris [Discrete Math. 69 (1988), 97-99]