Expansions of chromatic polynomials and log-concavity
نویسندگان
چکیده
منابع مشابه
Expansions of Chromatic Polynomials and Log-concavity
In this paper we present several results and open problems about logconcavity properties of sequences associated with graph colorings. Five polynomials intimately related to the chromatic polynomial of a graph are introduced and their zeros, combinatorial and log-concavity properties are studied. Four of these polynomials have never been considered before in the literature and some yield new ex...
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In a paper from 1912 aimed at proving the four-color theorem, G. D. Birkhoff [Birkhoff 12] introduced a function P (G, x), defined for all positive integers x to be the number of proper x-colorings of the graph G. As it turns out, P (G, x) is a polynomial in x and so is defined for all real and complex values of x as well. Of course, P (G, x) is the by now well-known chromatic polynomial, and a...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1992
ISSN: 0002-9947,1088-6850
DOI: 10.1090/s0002-9947-1992-1069745-7