English

Cooperative conditions for the existence of rainbow matchings

Combinatorics 2021-12-30 v2

Abstract

Let k>1k>1, and let F\mathcal{F} be a family of 2n+k32n+k-3 non-empty sets of edges in a bipartite graph. If the union of every kk members of F\mathcal{F} contains a matching of size nn, then there exists an F\mathcal{F}-rainbow matching of size nn. Replacing 2n+k32n+k-3 by 2n+k22n+k-2, the result is true also for k=1k=1, and it can be proved (for all kk) both topologically and by a relatively simple combinatorial argument. The main effort is in gaining the last 11, which makes the result sharp.

Keywords

Cite

@article{arxiv.2003.08247,
  title  = {Cooperative conditions for the existence of rainbow matchings},
  author = {Ron Aharoni and Joseph Briggs and Minho Cho and Jinha Kim},
  journal= {arXiv preprint arXiv:2003.08247},
  year   = {2021}
}