{ "id": "1212.2530", "version": "v2", "published": "2012-12-11T16:42:44.000Z", "updated": "2013-03-24T16:11:59.000Z", "title": "Pattern Avoidance in Ordered Set Partitions", "authors": [ "Anant Godbole", "Adam Goyt", "Jennifer Herdan", "Lara Pudwell" ], "comment": "19 pages, 2 figures; Now includes a proof of what was Conjecture 1, and a generalization thereof", "categories": [ "math.CO" ], "abstract": "In this paper we consider the enumeration of ordered set partitions avoiding a permutation pattern of length 2 or 3. We provide an exact enumeration for avoiding the permutation 12. We also give exact enumeration for ordered partitions with 3 blocks and ordered partitions with n-1 blocks avoiding a permutation of length 3. We use enumeration schemes to recursively enumerate 123-avoiding ordered partitions with any block sizes. Finally, we give some asymptotic results for the growth rates of the number of ordered set partitions avoiding a single pattern; including a Stanley-Wilf type that exhibits existence of such growth rates.", "revisions": [ { "version": "v2", "updated": "2013-03-24T16:11:59.000Z" } ], "analyses": { "subjects": [ "05A18", "05A05", "05A15", "05A16" ], "keywords": [ "pattern avoidance", "ordered partitions", "ordered set partitions avoiding", "growth rates", "exact enumeration" ], "note": { "typesetting": "TeX", "pages": 19, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1212.2530G" } } }