{ "id": "0706.1738", "version": "v2", "published": "2007-06-12T16:06:58.000Z", "updated": "2007-06-22T20:09:33.000Z", "title": "Permutations with Extremal number of Fixed Points", "authors": [ "Guo-Niu Han", "Guoce Xin" ], "comment": "minor change about corollary 3", "categories": [ "math.CO" ], "abstract": "We extend Stanley's work on alternating permutations with extremal number of fixed points in two directions: first, alternating permutations are replaced by permutations with a prescribed descent set; second, instead of simply counting permutations we study their generating polynomials by number of excedances. Several techniques are used: Desarmenien's desarrangement combinatorics, Gessel's hook-factorization and the analytical properties of two new permutation statistics \"DEZ\" and \"lec\". Explicit formulas for the maximal case are derived by using symmetric function tools.", "revisions": [ { "version": "v2", "updated": "2007-06-22T20:09:33.000Z" } ], "analyses": { "subjects": [ "05A05", "05A15", "05E05" ], "keywords": [ "extremal number", "fixed points", "extend stanleys work", "alternating permutations", "desarmeniens desarrangement combinatorics" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2007arXiv0706.1738H" } } }