Expansions of Chromatic Polynomials and Log-concavity

نویسنده

  • FRANCESCO BRENTI
چکیده

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 expansions for the chromatic polynomial.

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تاریخ انتشار 2010