English

Rainbow spanning trees in random subgraphs of dense regular graphs

Combinatorics 2023-01-10 v3

Abstract

We consider the following random model for edge-colored graphs. A graph GG on nn vertices is fixed, and a random subgraph GpG_p is chosen by letting each edge of GG remain independently with probability pp. Then, each edge of GpG_p is colored uniformly at random from the set [n1][n-1]. A result of Frieze and McKay (Random Structures and Algorithms, 1994) implies that when G=KnG = K_n and p=(2+ϵ)lognnp = (2 + \epsilon) \frac{\log n}{n} for some constant ϵ>0\epsilon > 0, then GpG_p almost surely contains a rainbow spanning tree. In this paper, we show that if GG is a dd-regular Ω(n)\Omega(n)-edge-connected graph, then when p=(2+ϵ)logndp = (2 + \epsilon) \frac {\log n}{d} for some constant ϵ>0\epsilon > 0, GpG_p almost surely contains a rainbow spanning tree. Our main tool is a new edge-replacement method for rainbow forests.

Keywords

Cite

@article{arxiv.2102.12012,
  title  = {Rainbow spanning trees in random subgraphs of dense regular graphs},
  author = {Peter Bradshaw},
  journal= {arXiv preprint arXiv:2102.12012},
  year   = {2023}
}

Comments

11 pages, 1 figure

R2 v1 2026-06-23T23:27:26.333Z