Graphs with $\alpha_1$ and $\tau_1$ both large
Abstract
Given a graph , let denote the smallest size of a set of edges whose deletion makes triangle-free, and let denote the largest size of an edge set containing at most one edge from each triangle of . Erd\H{o}s, Gallai, and Tuza introduced several problems with the unifying theme that and cannot both be "very large"; the most well-known such problem is their conjecture that , which was proved by Norin and Sun. We consider three other problems within this theme (two introduced by Erd\H{o}s, Gallai, and Tuza, another by Norin and Sun), all of which request an upper bound either on or on for some constant , and prove the existence of graphs for which these quantities are "large".
Keywords
Cite
@article{arxiv.1705.04745,
title = {Graphs with $\alpha_1$ and $\tau_1$ both large},
author = {Gregory J. Puleo},
journal= {arXiv preprint arXiv:1705.04745},
year = {2018}
}
Comments
6 pages; improved exposition a bit and fixed an issue regarding integrality from the earlier version