{ "id": "1704.00487", "version": "v1", "published": "2017-04-03T09:17:47.000Z", "updated": "2017-04-03T09:17:47.000Z", "title": "On the independence number of graphs related to a polarity", "authors": [ "Sam Mattheus", "Francesco Pavese", "Leo Storme" ], "categories": [ "math.CO" ], "abstract": "We investigate the independence number of two graphs constructed from a polarity of $\\mathrm{PG}(2,q)$. For the first graph under consideration, the Erd\\H{o}s-R\\'enyi graph $ER_q$, we provide an improvement on the known lower bounds on its independence number. In the second part of the paper we consider the Erd\\H{o}s-R\\'enyi hypergraph of triangles $\\mathcal{H}_q$. We determine the exact magnitude of the independence number of $\\mathcal{H}_q$, $q$ even. This solves a problem posed by Mubayi and Williford.", "revisions": [ { "version": "v1", "updated": "2017-04-03T09:17:47.000Z" } ], "analyses": { "subjects": [ "05C50", "05B25", "05C69", "05C35" ], "keywords": [ "independence number", "first graph", "lower bounds", "second part", "exact magnitude" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }