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Lower Bound on the Chromatic Number by Spectra of Weighted Adjacency Matrices

Pawel Wocjan·Dominik Janzing·Thomas Beth
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Abstract

A lower bound on the chromatic number of a graph is derived by majorization of spectra of weighted adjacency matrices. These matrices are given by Hadamard products of the adjacency matrix and arbitrary Hermitian matrices.

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Pawel Wocjan, Dominik Janzing, Thomas Beth. 2001-12-21. Lower Bound on the Chromatic Number by Spectra of Weighted Adjacency Matrices. https://arxiv.org/abs/cs/0112023

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