Adjacent Vertex Distinguishing Edge-Coloring of Planar Graphs with Girth at Least Five

Xinping Xu1, Yiying Zhang2
1Department of Mathematics and Computer Science, Jiangsu Second Normal University, Nanjing, 210013, China
2Institute of Mathematics, School of Mathematical Sciences Nanjing Normal University, Nanjing, 210046, China

Abstract

An adjacent vertex-distinguishing edge coloring ,avd-coloring for short, of a graph \(G\) is a proper edge coloring of \(G\) such that no pair of adjacent vertices are incident to the same set of colors. We denote the avd-chromatic number of \(G\) by \(\chi’_{avd}(G)\), which is the smallest integer \(k\) such that \(G\) has an avd-coloring with \(k\) colors, and the maximum degree of \(G\) by \(\Delta(G)\). In this paper, we prove that \(\chi’_{avd}(G) \leq \Delta(G) + 4\) for every planar graph \(G\) without isolated edges whose girth is at least five. Notably, this bound is nearly sharp, as \(\chi’_{avd}(C_5) = \Delta(C_5) + 3\).