Panchromatic patterns by paths
Abstract
Let be a digraph, possibly with loops, and let be a loopless multidigraph with a colouring of its arcs . An -path of is a path of such that is an arc of for every . For , we say that reaches by -paths if there exists an -path from to in . A subset is -absorbent of if every vertex in reaches by -paths some vertex in , and it is -independent if no vertex in can reach another (different) vertex in by -pahts. An -kernel is an independent by -paths and absorbent by -paths subset of . We define as the set of digraphs such that any -arc-coloured tournament has an -absorbent by paths vertex; the set consists of the digraphs such that any -arc-coloured digraph has an independent, -absorbent by paths set; analogously, the set is the set of digraphs such that every -arc-coloured digraph contains an -kernel by paths. In this work, we present a characterization of , and provide structural properties of the digraphs in which settle up its characterization except for the analysis of a single digraph on three vertices.
Cite
@article{arxiv.1903.10031,
title = {Panchromatic patterns by paths},
author = {Germán Benítez-Bobadilla and Hortensia Galeana-Sánchez and César Hernández-Cruz},
journal= {arXiv preprint arXiv:1903.10031},
year = {2019}
}
Comments
27 pages, 9 figures