English

The hitting time of rainbow connection number two

Combinatorics 2012-12-10 v1

Abstract

In a graph GG with a given edge colouring, a rainbow path is a path all of whose edges have distinct colours. The minimum number of colours required to colour the edges of GG so that every pair of vertices is joined by at least one rainbow path is called the rainbow connection number rc(G)rc(G) of the graph GG. For any graph GG, rc(G)diam(G)rc(G) \ge diam(G). We will show that for the Erd\H{o}s-R\'enyi random graph G(n,p)G(n,p) close to the diameter 2 threshold, with high probability if diam(G)=2diam(G)=2 then rc(G)=2rc(G)=2. In fact, further strengthening this result, we will show that in the random graph process, with high probability the hitting times of diameter 2 and of rainbow connection number 2 coincide.

Keywords

Cite

@article{arxiv.1209.2981,
  title  = {The hitting time of rainbow connection number two},
  author = {Annika Heckel and Oliver Riordan},
  journal= {arXiv preprint arXiv:1209.2981},
  year   = {2012}
}

Comments

16 pages, 2 figures