{ "id": "1209.2471", "version": "v1", "published": "2012-09-12T00:53:03.000Z", "updated": "2012-09-12T00:53:03.000Z", "title": "Every 4-regular graph is acyclically edge-6-colorable", "authors": [ "Wang Weifan", "Shu Qiaojun", "Wang Yiqiao" ], "comment": "24 pages, 9 figures", "categories": [ "math.CO", "cs.DM" ], "abstract": "An acyclic edge coloring of a graph $G$ is a proper edge coloring such that no bichromatic cycles are produced. The acyclic chromatic index $a'(G)$ of $G$ is the smallest integer $k$ such that $G$ has an acyclic edge coloring using $k$ colors. Fiam${\\rm \\check{c}}$ik (1978) and later Alon, Sudakov and Zaks (2001) conjectured that $a'(G)\\le \\Delta + 2$ for any simple graph $G$ with maximum degree $\\Delta$. Basavaraju and Chandran (2009) showed that every graph $G$ with $\\Delta=4$, which is not 4-regular, satisfies the conjecture. In this paper, we settle the 4-regular case, i.e., we show that every 4-regular graph $G$ has $a'(G)\\le 6$.", "revisions": [ { "version": "v1", "updated": "2012-09-12T00:53:03.000Z" } ], "analyses": { "keywords": [ "acyclic edge coloring", "acyclic chromatic index", "conjecture", "maximum degree", "proper edge" ], "note": { "typesetting": "TeX", "pages": 24, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1209.2471W" } } }