{ "id": "1202.3082", "version": "v1", "published": "2012-02-14T16:38:24.000Z", "updated": "2012-02-14T16:38:24.000Z", "title": "Spanning trees with many leaves: new lower bounds in terms of number of vertices of degree~3 and at least~4", "authors": [ "D. V. Karpov" ], "comment": "33 pages, 15 figures", "journal": "Journal of Mathematical Sciences, Volume 196, Issue 6 (2014), pp 747-767", "doi": "10.1007/s10958-014-1691-8", "categories": [ "math.CO", "cs.DM" ], "abstract": "We prove, that every connected graph with $s$ vertices of degree 3 and $t$ vertices of degree at least~4 has a spanning tree with at least ${2\\over 5}t +{1\\over 5}s+\\alpha$ leaves, where $\\alpha \\ge {8\\over 5}$. Moreover, $\\alpha \\ge 2$ for all graphs besides three exclusions. All exclusion are regular graphs of degree~4, they are explicitly described in the paper. We present infinite series of graphs, containing only vertices of degrees~3 and~4, for which the maximal number of leaves in a spanning tree is equal for ${2\\over 5}t +{1\\over 5}s+2$. Therefore we prove that our bound is tight.", "revisions": [ { "version": "v1", "updated": "2012-02-14T16:38:24.000Z" } ], "analyses": { "subjects": [ "05C05" ], "keywords": [ "spanning tree", "lower bounds", "maximal number", "regular graphs", "infinite series" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 33, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1202.3082K" } } }