English

The digrundy number of digraphs

Combinatorics 2021-03-23 v1

Abstract

We extend the Grundy number and the ochromatic number, parameters on graph colorings, to digraph colorings, we call them {\emph{digrundy number}} and {\emph{diochromatic number}}, respectively. First, we prove that for every digraph the diochromatic number equals the digrundy number (as it happen for graphs). Then, we prove the interpolation property and the Nordhaus-Gaddum relations for the digrundy number, and improve the Nordhaus-Gaddum relations for the dichromatic and diachromatic numbers bounded previously by the authors in [Electron. J. Combin. 25 (2018) no. 3, Paper {\#} 3.51, 17 pp.]

Keywords

Cite

@article{arxiv.2103.11917,
  title  = {The digrundy number of digraphs},
  author = {Gabriela Araujo-Pardo and Juan José Montellano-Ballesteros and Mika Olsen and Christian Rubio-Montiel},
  journal= {arXiv preprint arXiv:2103.11917},
  year   = {2021}
}

Comments

9 pages, 1 figure

R2 v1 2026-06-24T00:25:45.334Z