English

Rainbow spanning structures in strongly edge-colored graphs

Combinatorics 2026-01-23 v1

Abstract

An edge-colored graph is a graph in which each edge is assigned a color. Such a graph is called strongly edge-colored if each color class forms an induced matching, and called rainbow if all edges receive pairwise distinct colors. In this paper, by establishing a connection with μn\mu n-bounded graphs, we prove that for all sufficiently large integers nn, every strongly edge-colored graph GG on nn vertices with minimum degree at least n+12\frac{n+1}{2} contains a rainbow Hamilton cycle. We also characterize all strongly edge-colored graphs on nn vertices with minimum degree exactly n2\frac{n}{2} that do not contain a rainbow Hamilton cycle. As an application, we determine the optimal minimum degree conditions for the existence of rainbow Hamilton paths and rainbow perfect matchings in strongly edge-colored graphs. Together, these results verify three conjectures concerning strongly edge-colored graphs for sufficiently large nn.

Keywords

Cite

@article{arxiv.2601.16084,
  title  = {Rainbow spanning structures in strongly edge-colored graphs},
  author = {Laihao Ding and Xiaolan Hu and Suyun Jiang},
  journal= {arXiv preprint arXiv:2601.16084},
  year   = {2026}
}

Comments

11 pages

R2 v1 2026-07-01T09:16:04.105Z