{ "id": "1004.2312", "version": "v1", "published": "2010-04-14T04:14:21.000Z", "updated": "2010-04-14T04:14:21.000Z", "title": "Note on the Rainbow $k$-Connectivity of Regular Complete Bipartite Graphs", "authors": [ "Xueliang Li", "Yuefang Sun" ], "comment": "6 pages", "categories": [ "math.CO", "cs.DM" ], "abstract": "A path in an edge-colored graph $G$, where adjacent edges may be colored the same, is called a rainbow path if no two edges of the path are colored the same. For a $\\kappa$-connected graph $G$ and an integer $k$ with $1\\leq k\\leq \\kappa$, the rainbow $k$-connectivity $rc_k(G)$ of $G$ is defined as the minimum integer $j$ for which there exists a $j$-edge-coloring of $G$ such that any two distinct vertices of $G$ are connected by $k$ internally disjoint rainbow paths. Denote by $K_{r,r}$ an $r$-regular complete bipartite graph. Chartrand et al. in \"G. Chartrand, G.L. Johns, K.A. McKeon, P. Zhang, The rainbow connectivity of a graph, Networks 54(2009), 75-81\" left an open question of determining an integer $g(k)$ for which the rainbow $k$-connectivity of $K_{r,r}$ is 3 for every integer $r\\geq g(k)$. This short note is to solve this question by showing that $rc_k(K_{r,r})=3$ for every integer $r\\geq 2k\\lceil\\frac{k}{2}\\rceil$, where $k\\geq 2$ is a positive integer.", "revisions": [ { "version": "v1", "updated": "2010-04-14T04:14:21.000Z" } ], "analyses": { "subjects": [ "05C15", "05C40" ], "keywords": [ "regular complete bipartite graph", "connectivity", "internally disjoint rainbow paths", "adjacent edges", "distinct vertices" ], "note": { "typesetting": "TeX", "pages": 6, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1004.2312L" } } }