2023/06/27 by Qiaojun Shu, Shu, Qiaojun, Guohui Lin +1
Computer Science · #Advanced Graph Theory Research #Combinatorics (math.CO) #Data Structures and Algorithms (cs.DS) #Discrete Mathematics (cs.DM) #FOS: Computer and information sciences #FOS: Mathematics
paper · pdf · doi:10.48550/arxiv.2306.15813
openalex publication_date 2023/06/27 · openalex created_date 2023/06/30 · openalex updated_date 2026/07/28
An edge coloring of a graph G is to color all the edges in the graph such that adjacent edges receive different colors. It is acyclic if each cycle in the graph receives at least three colors. Fiamčik (1978) and Alon, Sudakov and Zaks (2001) conjectured that every simple graph with maximum degree Δ is acyclically edge (Δ+ 2)-colorable -- the well-known acyclic edge coloring conjecture (AECC). Despite many major breakthroughs and minor improvements, the conjecture remains open even for planar graphs. In this paper, we prove that planar graphs are acyclically edge (Δ+ 5)-colorable. Our proof has two main steps: Using discharging methods, we first show that every non-trivial planar graph must have one of the eight groups of well characterized local structures; and then acyclically edge color the graph using no more than Δ+ 5 colors by an induction on the number of edges.