Triangle-free graphs of tree-width t are ⌈(t+3)∕2⌉-colorable
نویسندگان
چکیده
منابع مشابه
A Class of Three-Colorable Triangle-Free Graphs
The chromatic number of a triangle-free graph can be arbitrarily large. In this paper we show that if all subdivisions of K2,3 are also excluded as induced subgraphs, then the chromatic number becomes bounded by 3. We give a structural characterization of this class of graphs, from which we derive an O(nm) coloring algorithm, where n denotes the number of vertices and m the number of edges of t...
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 2017
ISSN: 0195-6698
DOI: 10.1016/j.ejc.2017.06.016