{ "id": "1512.08215", "version": "v1", "published": "2015-12-27T13:13:15.000Z", "updated": "2015-12-27T13:13:15.000Z", "title": "A characterization of A_5 by its Same-order type", "authors": [ "L. Jafari Taghvasani", "M. Zarrin" ], "comment": "5 pages", "categories": [ "math.GR" ], "abstract": "Let G be a group, de?ne an equivalence relation s as below: 8 g; h 2 G g s h () jgj = jhj the set of sizes of equivalence classes with respect to this relation is called the same-order type of G. Shen et al. (Monatsh. Math. 160 (2010), 337-341.), showed that A5 is the only group with the same-order type f1; 15; 20; 24g. In this paper, among other things, we prove that a nonabelian simple group G has same-order type fr; m; n; kg if and only if G ?= A5.", "revisions": [ { "version": "v1", "updated": "2015-12-27T13:13:15.000Z" } ], "analyses": { "subjects": [ "20D60", "20D06" ], "keywords": [ "characterization", "same-order type f1", "nonabelian simple group", "same-order type fr", "equivalence relation" ], "note": { "typesetting": "TeX", "pages": 5, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2015arXiv151208215J" } } }