{ "id": "1310.1368", "version": "v1", "published": "2013-10-04T18:40:08.000Z", "updated": "2013-10-04T18:40:08.000Z", "title": "A note on random greedy coloring of uniform hypergraphs", "authors": [ "Danila D. Cherkashin", "Jakub Kozik" ], "categories": [ "math.CO", "cs.DM" ], "abstract": "The smallest number of edges forming an n-uniform hypergraph which is not r-colorable is denoted by m(n,r). Erd\\H{o}s and Lov\\'{a}sz conjectured that m(n,2)=\\theta(n 2^n)$. The best known lower bound m(n,2)=\\Omega(sqrt(n/log(n)) 2^n) was obtained by Radhakrishnan and Srinivasan in 2000. We present a simple proof of their result. The proof is based on analysis of random greedy coloring algorithm investigated by Pluh\\'ar in 2009. The proof method extends to the case of r-coloring, and we show that for any fixed r we have m(n,r)=\\Omega((n/log(n))^(1-1/r) r^n) improving the bound of Kostochka from 2004. We also derive analogous bounds on minimum edge degree of an n-uniform hypergraph that is not r-colorable.", "revisions": [ { "version": "v1", "updated": "2013-10-04T18:40:08.000Z" } ], "analyses": { "subjects": [ "05C15", "05C65", "05D40", "G.2.1", "G.2.2", "G.3" ], "keywords": [ "uniform hypergraphs", "n-uniform hypergraph", "proof method extends", "random greedy coloring algorithm", "minimum edge degree" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013arXiv1310.1368C" } } }