Multiple DP-Coloring of Planar Graphs Without 3-Cycles and Normally Adjacent 4-Cycles
نویسندگان
چکیده
The concept of DP-coloring a graph is generalization list coloring introduced by Dvořák and Postle (J. Combin. Theory Ser. B 129, 38–54, 2018). Multiple graphs, as multiple coloring, was first studied Bernshteyn, Kostochka Zhu Graph 93, 203–221, 2020). This paper proves that planar graphs without 3-cycles normally adjacent 4-cycles are (7m, 2m)-DP-colorable for every integer m. As consequence, the strong fractional choice number any at most 7/2.
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ژورنال
عنوان ژورنال: Graphs and Combinatorics
سال: 2022
ISSN: ['1435-5914', '0911-0119']
DOI: https://doi.org/10.1007/s00373-022-02575-y