{ "id": "math/0603520", "version": "v3", "published": "2006-03-21T19:07:08.000Z", "updated": "2006-07-05T20:32:17.000Z", "title": "Alternating permutations and symmetric functions", "authors": [ "Richard P. Stanley" ], "comment": "37 pages, one figure. Correction of gap in the proof of Corollary 6.4, and some further minor corrections", "categories": [ "math.CO" ], "abstract": "We use the theory of symmetric functions to enumerate various classes of alternating permutations w of {1,2,...,n}. These classes include the following: (1) both w and w^{-1} are alternating, (2) w has certain special shapes, such as (m-1,m-2,...,1), under the RSK algorithm, (3) w has a specified cycle type, and (4) w has a specified number of fixed points. We also enumerate alternating permutations of a multiset. Most of our formulas are umbral expressions where after expanding the expression in powers of a variable E, E^k is interpreted as the Euler number E_k. As a small corollary, we obtain a combinatorial interpretation of the coefficients of an asymptotic expansion appearing in Ramanujan's Lost Notebook.", "revisions": [ { "version": "v3", "updated": "2006-07-05T20:32:17.000Z" } ], "analyses": { "subjects": [ "05A15", "05A40", "05E05" ], "keywords": [ "symmetric functions", "ramanujans lost notebook", "special shapes", "rsk algorithm", "specified cycle type" ], "note": { "typesetting": "TeX", "pages": 37, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2006math......3520S" } } }