{ "id": "1807.04997", "version": "v1", "published": "2018-07-13T10:32:11.000Z", "updated": "2018-07-13T10:32:11.000Z", "title": "MAX for $k$-independence in multigraphs", "authors": [ "Nevena Francetić", "Sara Herke", "Daniel Horsley" ], "comment": "16 pages, 5 figures", "categories": [ "math.CO" ], "abstract": "For a fixed positive integer $k$, a set $S$ of vertices of a graph or multigraph is called a {\\it $k$-independent set} if the subgraph induced by $S$ has maximum degree less than $k$. The well-known algorithm MAX finds a maximal $k$-independent set in a graph or multigraph by iteratively removing vertices of maximum degree until what remains has maximum degree less than $k$. We give an efficient procedure that determines, for a given degree sequence $D$, the smallest cardinality $b(D)$ of a $k$-independent set that can result from any application of MAX to any loopless multigraph with degree sequence $D$. This analysis of the worst case is sharp for each degree sequence $D$ in that there exists a multigraph $G$ with degree sequence $D$ such that some application of MAX to $G$ will result in a $k$-independent set of cardinality exactly $b(D)$.", "revisions": [ { "version": "v1", "updated": "2018-07-13T10:32:11.000Z" } ], "analyses": { "subjects": [ "05C69", "05B40" ], "keywords": [ "degree sequence", "multigraph", "independent set", "maximum degree", "well-known algorithm max finds" ], "note": { "typesetting": "TeX", "pages": 16, "language": "en", "license": "arXiv", "status": "editable" } } }