Majority choosability of digraphs
Abstract
A \emph{majority coloring} of a digraph is a coloring of its vertices such that for each vertex , at most half of the out-neighbors of has the same color as . A digraph is \emph{majority -choosable} if for any assignment of lists of colors of size to the vertices there is a majority coloring of from these lists. We prove that every digraph is majority -choosable. This gives a positive answer to a question posed recently by Kreutzer, Oum, Seymour, van der Zypen, and Wood in \cite{Kreutzer}. We obtain this result as a consequence of a more general theorem, in which majority condition is profitably extended. For instance, the theorem implies also that every digraph has a coloring from arbitrary lists of size three, in which at most of the out-neighbors of any vertex share its color. This solves another problem posed in \cite{Kreutzer}, and supports an intriguing conjecture stating that every digraph is majority -colorable.
Cite
@article{arxiv.1608.06912,
title = {Majority choosability of digraphs},
author = {Marcin Anholcer and Bartłomiej Bosek and Jarosław Grytczuk},
journal= {arXiv preprint arXiv:1608.06912},
year = {2018}
}