Unified spectral bounds on the chromatic number
نویسندگان
چکیده
منابع مشابه
Unified spectral bounds on the chromatic number
One of the best known results in spectral graph theory is the following lower bound on the chromatic number due to Alan Hoffman, where μ1 and μn are respectively the maximum and minimum eigenvalues of the adjacency matrix: χ ≥ 1+μ1/−μn. We recently generalised this bound to include all eigenvalues of the adjacency matrix. In this paper, we further generalize these results to include all eigenva...
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The purpose of this paper is to discuss spectral bounds on the chromatic number of a graph. The classic result by Hoffman, where λ1 and λn are respectively the maximum and minimum eigenvalues of the adjacency matrix of a graph G, is χ(G) ≥ 1− λ1 λn . It is possible to discuss the coloring of Hermitian matrices in general. Nikiforov developed a spectral bound on the chromatic number of such matr...
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ژورنال
عنوان ژورنال: Discussiones Mathematicae Graph Theory
سال: 2015
ISSN: 1234-3099,2083-5892
DOI: 10.7151/dmgt.1835