English

Rainbow paths and large rainbow matchings

Combinatorics 2021-10-08 v3

Abstract

A conjecture of the first two authors is that nn matchings of size nn in any graph have a rainbow matching of size n1n-1. We prove a lower bound of 23n1\frac{2}{3}n-1, improving on the trivial 12n\frac{1}{2}n, and an analogous result for hypergraphs. For {C3,C5}\{C_3,C_5\}-free graphs and for disjoint matchings we obtain a lower bound of 3n4O(1)\frac{3n}{4}-O(1). We also discuss a conjecture on rainbow alternating paths, that if true would yield a lower bound of n2nn-\sqrt{2n}. We prove the non-alternating (ordinary paths) version of this conjecture.

Keywords

Cite

@article{arxiv.2012.14992,
  title  = {Rainbow paths and large rainbow matchings},
  author = {Ron Aharoni and Eli Berger and Maria Chudnovsky and Shira Zerbib},
  journal= {arXiv preprint arXiv:2012.14992},
  year   = {2021}
}
R2 v1 2026-06-23T21:34:47.720Z