{ "id": "0801.1744", "version": "v1", "published": "2008-01-11T10:17:27.000Z", "updated": "2008-01-11T10:17:27.000Z", "title": "Acyclic Edge Coloring of Graphs with Maximum Degree 4", "authors": [ "Manu Basavaraju", "L. Sunil Chandran" ], "comment": "13 pages", "categories": [ "math.CO" ], "abstract": "An $acyclic$ edge coloring of a graph is a proper edge coloring such that there are no bichromatic cycle s. The \\emph{acyclic chromatic index} of a graph is the minimum number k such that there is an acyclic e dge coloring using k colors and is denoted by $a'(G)$. It was conjectured by Alon, Sudakov and Zaks that for any simple and finite graph $G$, $a'(G)\\le \\Delta+2$, where $\\Delta =\\Delta(G)$ denotes the maximum degree of $G$. We prove the conjecture for connected graphs with $\\Delta(G) \\le 4$, with the additional restriction that $m \\le 2n-1$, where $n$ is the number of vertices and $m$ is the number of edges in $G $. Note that for any graph $G$, $m \\le 2n$, when $\\Delta(G) \\le 4$. It follows that for any graph $G$ if $\\Delta(G) \\le 4$, then $a'(G) \\le 7$.", "revisions": [ { "version": "v1", "updated": "2008-01-11T10:17:27.000Z" } ], "analyses": { "keywords": [ "maximum degree", "acyclic edge coloring", "chromatic index", "additional restriction", "minimum number" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable" } } }