Certificates of Factorisation for Chromatic Polynomials
نویسندگان
چکیده
منابع مشابه
Certificates of Factorisation for Chromatic Polynomials
The chromatic polynomial gives the number of proper λ-colourings of a graph G. This paper considers factorisation of the chromatic polynomial as a first step in an algebraic study of the roots of this polynomial. The chromatic polynomial of a graph is said to have a chromatic factorisation if P (G,λ) = P (H1, λ)P (H2, λ)/P (Kr , λ) for some graphs H1 and H2 and clique Kr. It is known that the c...
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The chromatic polynomial P (G,λ) gives the number of λ-colourings of a graph. If P (G,λ) = P (H1, λ)P (H2, λ)/P (Kr , λ), then the graph G is said to have a chromatic factorisation with chromatic factors H1 and H2. It is known that the chromatic polynomial of any clique-separable graph has a chromatic factorisation. In this paper we construct an infinite family of graphs that have chromatic fac...
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ژورنال
عنوان ژورنال: The Electronic Journal of Combinatorics
سال: 2009
ISSN: 1077-8926
DOI: 10.37236/163