Article ID Journal Published Year Pages File Type
4646889 Discrete Mathematics 2014 5 Pages PDF
Abstract
Recently, Kim and Park have found an infinite family of graphs whose squares are not chromatic-choosable. Xuding Zhu asked whether there is some k such that all kth power graphs are chromatic-choosable. We answer this question in the negative: we show that there is a positive constant c such that for any k there is a family of graphs G with χ(Gk) unbounded and χℓ(Gk)≥cχ(Gk)logχ(Gk). We also provide an upper bound, χℓ(Gk)<χ(Gk)3 for k>1.
Related Topics
Physical Sciences and Engineering Mathematics Discrete Mathematics and Combinatorics
Authors
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