The intersection graph of ideals of $\mathbb{Z}_n$ is\\ weakly perfect
Commutative Algebra
2013-05-28 v1 Combinatorics
Abstract
A graph is called weakly perfect if its vertex chromatic number equals its clique number. Let be a ring and be the set of all left proper non-trivial ideals of . The intersection graph of ideals of , denoted by , is a graph with the vertex set and two distinct vertices and are adjacent if and only if . In this paper, it is shown that , for every positive integer , is a weakly perfect graph. Also, for some values of , we give an explicit formula for the vertex chromatic number of . Furthermore, it is proved that the edge chromatic number of is equal to the maximum degree of unless either is a null graph with two vertices or a complete graph of odd order.
Keywords
Cite
@article{arxiv.1305.6287,
title = {The intersection graph of ideals of $\mathbb{Z}_n$ is\\ weakly perfect},
author = {R. Nikandish and M. J. Nikmehr},
journal= {arXiv preprint arXiv:1305.6287},
year = {2013}
}
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8 pages