{ "id": "math/0409480", "version": "v2", "published": "2004-09-24T19:06:47.000Z", "updated": "2005-03-02T22:31:32.000Z", "title": "Dissecting the Stanley Partition Function", "authors": [ "Alexander Berkovich", "Frank G. Garvan" ], "comment": "13 pages, new theorems, examples and Note added, to appear in JCT(A)", "categories": [ "math.CO", "math.NT" ], "abstract": "Let p(n) denote the number of unrestricted partitions of n. For i=0, 2, let p[i](n) denote the number of partitions pi of n such that O(pi) - O(pi') = i mod 4. Here O(pi) denotes the number of odd parts of the partition pi and pi' is the conjugate of pi. R. Stanley [13], [14] derived an infinite product representation for the generating function of p[0](n)-p[2](n). Recently, Holly Swisher[15] employed the circle method to show that limit[n->oo] p[0](n)/p(n) = 1/2 (i) and that for sufficiently large n 2 p[0](n) > p(n), if n=0,1 mod 4, 2 p[0](n) < p(n), otherwise. (ii) In this paper we study even/odd dissection of the Stanley product, and show how to use it to prove (i) and (ii) with no restriction on n. Moreover, we establish the following new result |p[0](2n) - p[2](2n)| > |p[0](2n+1) - p[2](2n+1)|, n>0. Two proofs of this surprising inequality are given. The first one uses the Gollnitz-Gordon partition theorem. The second one is an immediate corollary of a new partition inequality, which we prove in a combinatorial manner. Our methods are elementary. We use only Jacobi's triple product identity and some naive upper bound estimates.", "revisions": [ { "version": "v2", "updated": "2005-03-02T22:31:32.000Z" } ], "analyses": { "subjects": [ "11P81", "11P82", "11P83", "05A17", "05A19" ], "keywords": [ "stanley partition function", "jacobis triple product identity", "gollnitz-gordon partition theorem", "naive upper bound estimates", "infinite product representation" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2004math......9480B" } } }