(2,3) Cordial Trees and Paths
Combinatorics
2021-05-12 v2
Abstract
Recently L. B. Beasley introduced -cordial labelings of directed graphs in [1]. He made two conjectures which we resolve in this article. He conjectured that every orientation of a path of length at least five is cordial, and that every tree of max degree has a cordial orientation. We show these two conjectures to be false. We also discuss the cordiality of orientations of the Petersen graph, and establish an upper bound for the number of edges a graph can have and still be cordial. An application of cordial labelings is also presented.
Keywords
Cite
@article{arxiv.2012.10591,
title = {(2,3) Cordial Trees and Paths},
author = {Manuel Santana and Jonathan Mousley and David Brown and Leroy Beasley},
journal= {arXiv preprint arXiv:2012.10591},
year = {2021}
}