English

Subdivisions with congruence constraints in digraphs of large chromatic number

Combinatorics 2022-08-15 v1

Abstract

We prove that for every digraph FF and every assignment of pairs of integers (re,qe)eA(F)(r_e,q_e)_{e \in A(F)} to its arcs there exists an integer NN such that every digraph DD with dichromatic number at least NN contains a subdivision of FF in which ee is subdivided into a directed path of length congruent to rer_e modulo qeq_e, for every eA(F)e \in A(F). This generalizes to the directed setting the analogous result by Thomassen for undirected graphs, and at the same time yields a novel short proof of his result.

Keywords

Cite

@article{arxiv.2208.06358,
  title  = {Subdivisions with congruence constraints in digraphs of large chromatic number},
  author = {Raphael Steiner},
  journal= {arXiv preprint arXiv:2208.06358},
  year   = {2022}
}

Comments

5 pages, no figures