Infinitely many counterexamples to a conjecture of Lov\'asz
Combinatorics
2025-07-16 v2
Abstract
Motivated by the well-known conjecture of Ryser which relates maximum matchings to minimum vertex covers in -partite -uniform hypergraphs, Lov\'asz formulated a stronger conjecture. It states that one can always reduce the matching number by removing vertices. This conjecture was very recently disproven for by Clow, Haxell, and Mohar using the line graph of a -regular graph of order . Building on this, we describe a simple infinite family of counterexamples based on generalized Petersen graphs for the case and give specific counterexamples for .
Keywords
Cite
@article{arxiv.2506.21286,
title = {Infinitely many counterexamples to a conjecture of Lov\'asz},
author = {Aida Abiad and Frederik Garbe and Xavier Povill and Christoph Spiegel},
journal= {arXiv preprint arXiv:2506.21286},
year = {2025}
}