English

Extension from Precoloured Sets of Edges

Combinatorics 2018-05-29 v3

Abstract

We consider precolouring extension problems for proper edge-colourings of graphs and multigraphs, in an attempt to prove stronger versions of Vizing's and Shannon's bounds on the chromatic index of (multi)graphs in terms of their maximum degree Δ\Delta. We are especially interested in the following question: when is it possible to extend a precoloured matching to a colouring of all edges of a (multi)graph? This question turns out to be related to the notorious List Colouring Conjecture and other classic notions of choosability.

Keywords

Cite

@article{arxiv.1407.4339,
  title  = {Extension from Precoloured Sets of Edges},
  author = {Katherine Edwards and António Girão and Jan van den Heuvel and Ross J. Kang and Gregory J. Puleo and Jean-Sébastien Sereni},
  journal= {arXiv preprint arXiv:1407.4339},
  year   = {2018}
}

Comments

26 pages, 3 figures, 1 table; in v2, two co-authors added, main conjecture weakened, weak version of conjecture proved, planar section updated; v3 accepted to Electronic Journal of Combinatorics

R2 v1 2026-06-22T05:05:29.267Z