{ "id": "2002.03189", "version": "v1", "published": "2020-02-08T15:41:26.000Z", "updated": "2020-02-08T15:41:26.000Z", "title": "Maximizing the number of independent sets of fixed size in $K_n$-covered graphs", "authors": [ "Anyao Wang", "Xinmin Hou", "Boyuan Liu", "Yue Ma" ], "comment": "10 pages", "categories": [ "math.CO" ], "abstract": "A graph $G$ is $H$-covered by some given graph $H$ if each vertex in $G$ is contained in a copy of $H$. In this note, we give the maximum number of independent sets of size $t\\ge 3$ in $K_n$-covered graphs of size $N\\ge n+t-1$ and determine its extremal graph. The result answers a question proposed by Chakraborit and Loh. The proof uses an edge-switching operation of hypergraphs which remains the number of independent sets nondecreasing.", "revisions": [ { "version": "v1", "updated": "2020-02-08T15:41:26.000Z" } ], "analyses": { "subjects": [ "05C65", "05C69" ], "keywords": [ "covered graphs", "fixed size", "maximum number", "maximizing", "extremal graph" ], "note": { "typesetting": "TeX", "pages": 10, "language": "en", "license": "arXiv", "status": "editable" } } }