A note on a Brooks’ type theorem for DP-coloring
نویسندگان
چکیده
Dvořák and Postle [8] introduced aDP-coloring of a simple graph as a generalization of a list-coloring. They proved a Brooks’ type theorem for a DP-coloring, and Bernsheteyn, Kostochka and Pron [5] extended it to a DP-coloring of multigraphs. However, detailed structure when a multigraph does not admit a DP-coloring was not specified in [5]. In this note, we make this point clear and give the complete structure. This is also motivated by the relation to signed coloring of signed graphs.
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