English

The K\H{o}nig Graph Process

Combinatorics 2020-07-20 v2

Abstract

Say that a graph G has property K\mathcal{K} if the size of its maximum matching is equal to the order of a minimal vertex cover. We study the following process. Set N:=(n2)N:= \binom{n}{2} and let e1,e2,eNe_1, e_2, \dots e_{N} be a uniformly random ordering of the edges of KnK_n, with nn an even integer. Let G0G_0 be the empty graph on nn vertices. For m0m \geq 0, Gm+1G_{m+1} is obtained from GmG_m by adding the edge em+1e_{m+1} exactly if Gm{em+1}G_m \cup \{ e_{m+1}\} has property K\mathcal{K}. We analyse the behaviour of this process, focusing mainly on two questions: What can be said about the structure of GNG_N and for which mm will GmG_m contain a perfect matching?

Keywords

Cite

@article{arxiv.1906.04806,
  title  = {The K\H{o}nig Graph Process},
  author = {Nina Kamčev and Michael Krivelevich and Natasha Morrison and Benny Sudakov},
  journal= {arXiv preprint arXiv:1906.04806},
  year   = {2020}
}
R2 v1 2026-06-23T09:50:49.269Z