{ "id": "1206.3862", "version": "v4", "published": "2012-06-18T09:25:32.000Z", "updated": "2018-11-18T03:29:06.000Z", "title": "Total coloring of 1-toroidal graphs of maximum degree at least 11 and no adjacent triangles", "authors": [ "Tao Wang" ], "comment": "10 pages", "journal": "Journal of Combinatorial Optimization, 33 (2017) 1090--1105", "doi": "10.1007/s10878-016-0025-9", "categories": [ "math.CO", "cs.DM" ], "abstract": "A {\\em total coloring} of a graph $G$ is an assignment of colors to the vertices and the edges of $G$ such that every pair of adjacent/incident elements receive distinct colors. The {\\em total chromatic number} of a graph $G$, denoted by $\\chiup''(G)$, is the minimum number of colors in a total coloring of $G$. The well-known Total Coloring Conjecture (TCC) says that every graph with maximum degree $\\Delta$ admits a total coloring with at most $\\Delta + 2$ colors. A graph is {\\em $1$-toroidal} if it can be drawn in torus such that every edge crosses at most one other edge. In this paper, we investigate the total coloring of $1$-toroidal graphs, and prove that the TCC holds for the $1$-toroidal graphs with maximum degree at least~$11$ and some restrictions on the triangles. Consequently, if $G$ is a $1$-toroidal graph with maximum degree $\\Delta$ at least~$11$ and without adjacent triangles, then $G$ admits a total coloring with at most $\\Delta + 2$ colors.", "revisions": [ { "version": "v3", "updated": "2013-09-16T08:11:23.000Z", "abstract": "A {\\em total coloring} of a graph $G$ is an assignment of colors to the vertices and the edges of $G$ such that every pair of adjacent/incident elements receive distinct colors. The {\\em total chromatic number} of a graph $G$, denoted by $\\chiup''(G)$, is the minimum number of colors needed in a total coloring of $G$. The most well-known Total Coloring Conjecture (TCC) says that every graph with maximum degree $\\Delta$ admits a total coloring with at most $\\Delta + 2$ colors. A graph is {\\em 1-toroidal} if it can be drawn on torus such that every edge crosses at most one other edge. In this paper, we investigate the total coloring of 1-toroidal graphs, and prove that the TCC holds for the 1-toroidal graphs with maximum degree at least 11 and some restrictions on the triangles. Consequently, if $G$ is a 1-toroidal graph with maximum degree $\\Delta$ at least 11 and without adjacent triangles, then $G$ admits a total coloring with at most $\\Delta + 2$ colors.", "comment": "12 pages", "journal": null, "doi": null }, { "version": "v4", "updated": "2018-11-18T03:29:06.000Z" } ], "analyses": { "subjects": [ "05C15" ], "keywords": [ "maximum degree", "adjacent triangles", "adjacent/incident elements receive distinct colors", "total chromatic number", "well-known total coloring conjecture" ], "tags": [ "journal article" ], "publication": { "publisher": "Springer" }, "note": { "typesetting": "TeX", "pages": 10, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1206.3862W" } } }