{ "id": "1302.5503", "version": "v1", "published": "2013-02-22T07:33:57.000Z", "updated": "2013-02-22T07:33:57.000Z", "title": "Transversals of Longest Paths and Cycles", "authors": [ "Dieter Rautenbach", "Jean-Sébastien Sereni" ], "categories": [ "math.CO", "cs.DM" ], "abstract": "Let G be a graph of order n. Let lpt(G) be the minimum cardinality of a set X of vertices of G such that X intersects every longest path of G and define lct(G) analogously for cycles instead of paths. We prove that lpt(G) \\leq ceiling(n/4-n^{2/3}/90), if G is connected, lct(G) \\leq ceiling(n/3-n^{2/3}/36), if G is 2-connected, and \\lpt(G) \\leq 3, if G is a connected circular arc graph. Our bound on lct(G) improves an earlier result of Thomassen and our bound for circular arc graphs relates to an earlier statement of Balister \\emph{et al.} the argument of which contains a gap. Furthermore, we prove upper bounds on lpt(G) for planar graphs and graphs of bounded tree-width.", "revisions": [ { "version": "v1", "updated": "2013-02-22T07:33:57.000Z" } ], "analyses": { "keywords": [ "longest path", "transversals", "circular arc graphs relates", "connected circular arc graph", "earlier result" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013arXiv1302.5503R" } } }