DP-4-coloring of planar graphs with some restrictions on cycles [article]

Rui Li, Tao Wang
2019 arXiv   pre-print
DP-coloring was introduced by Dvořák and Postle as a generalization of list coloring. It was originally used to solve a longstanding conjecture by Borodin, stating that every planar graph without cycles of lengths 4 to 8 is 3-choosable. In this paper, we give three sufficient conditions for a planar graph is DP-4-colorable. Actually all the results (Theorem 1.3, 1.4 and 1.7) are stated in the "color extendability" form, and uniformly proved by vertex identification and discharging method.
arXiv:1909.08511v1 fatcat:752mrabtpfcorpaitrvtrpxlzi