On 2-defective DP-colorings of sparse graphs
نویسندگان
چکیده
Introduced by Dvořák and Postle, the notion of DP-coloring generalizes list coloring helps to prove new results on coloring. We consider 1-defective 2-defective DP-colorings graphs with 2 colors. For j=1,2, we find exact lower bounds number edges in (j,2)-DP-critical (that is, that do not admit j-defective colors but whose every proper subgraph has such a coloring) given vertices. These also hold for (j,2)-list-critical graphs, j=2 are better than previously known Havet Sereni (2006).
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 2021
ISSN: ['1095-9971', '0195-6698']
DOI: https://doi.org/10.1016/j.ejc.2020.103217