{ "id": "1407.0367", "version": "v1", "published": "2014-07-01T19:23:46.000Z", "updated": "2014-07-01T19:23:46.000Z", "title": "On the Roman Bondage Number of Graphs on surfaces", "authors": [ "Vladimir Samodivkin" ], "comment": "5 pages", "categories": [ "math.CO" ], "abstract": "A Roman dominating function on a graph $G$ is a labeling $f : V(G) \\rightarrow \\{0, 1, 2\\}$ such that every vertex with label $0$ has a neighbor with label $2$. The Roman domination number, $\\gamma_R(G)$, of $G$ is the minimum of $\\Sigma_{v\\in V (G)} f(v)$ over such functions. The Roman bondage number $b_R(G)$ is the cardinality of a smallest set of edges whose removal from $G$ results in a graph with Roman domination number not equal to $\\gamma_R(G)$. In this paper we obtain upper bounds on $b_{R}(G)$ in terms of (a) the average degree and maximum degree, and (b) Euler characteristic, girth and maximum degree. We also show that the Roman bondage number of every graph which admits a $2$-cell embedding on a surface with non negative Euler characteristic does not exceed $15$.", "revisions": [ { "version": "v1", "updated": "2014-07-01T19:23:46.000Z" } ], "analyses": { "subjects": [ "05C69" ], "keywords": [ "roman bondage number", "roman domination number", "maximum degree", "non negative euler characteristic", "smallest set" ], "note": { "typesetting": "TeX", "pages": 5, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1407.0367S" } } }