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arXiv · 2205.07968

$2$-distance, injective, and exact square list-coloring of planar graphs with maximum degree 4

Hoang La·Kenny Štorgel
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Abstract

In the past various distance based colorings on planar graphs were introduced. We turn our focus to three of them, namely $2$-distance coloring, injective coloring, and exact square coloring. A $2$-distance coloring is a proper coloring of the vertices in which no two vertices at distance $2$ receive the same color, an injective coloring is a coloring of the vertices in which no two vertices with a common neighbor receive the same color, and an exact square coloring is a coloring of the vertices in which no two vertices at distance exactly $2$ receive the same color. We prove that planar graphs with maximum degree $\Delta = 4$ and girth at least $4$ are $2$-distance list $(\Delta + 7)$-colorable and injectively list $(\Delta + 5)$-colorable. Additionally, we prove that planar graphs with $\Delta = 4$ are injectively list $(\Delta + 7)$-colorable and exact square list $(\Delta + 6)$-colorable.

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Hoang La, Kenny Štorgel. 2022-05-16. $2$-distance, injective, and exact square list-coloring of planar graphs with maximum degree 4. https://doi.org/10.1016/j.disc.2023.113405

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