Bispindles in strongly connected digraphs with large chromatic number
Combinatorics
2017-03-08 v1
Abstract
A -bispindle is the union of -dipaths and -dipaths, all these dipaths being pairwise internally disjoint. Recently, Cohen et al. showed that for every - bispindle , there exists an integer such that every strongly connected digraph with chromatic number greater than contains a subdivision of . We investigate generalisations of this result by first showing constructions of strongly connected digraphs with large chromatic number without any -bispindle or -bispindle. Then we show that strongly connected digraphs with large chromatic number contains a -bispindle, where at least one of the -dipaths and the -dipath are long.
Cite
@article{arxiv.1703.02230,
title = {Bispindles in strongly connected digraphs with large chromatic number},
author = {N. Cohenn and F. Havet and W. Lochet and R. Lopes},
journal= {arXiv preprint arXiv:1703.02230},
year = {2017}
}