{ "id": "math/0602293", "version": "v1", "published": "2006-02-14T09:31:19.000Z", "updated": "2006-02-14T09:31:19.000Z", "title": "h-vectors of generalized associahedra and non-crossing partitions", "authors": [ "Christos A. Athanasiadis", "Thomas Brady", "Jon McCammond", "Colum Watt" ], "comment": "20 pages, 1 figure", "categories": [ "math.CO" ], "abstract": "A case-free proof is given that the entries of the $h$-vector of the cluster complex $\\Delta (\\Phi)$, associated by S. Fomin and A. Zelevinsky to a finite root system $\\Phi$, count elements of the lattice $\\nc$ of noncrossing partitions of corresponding type by rank. Similar interpretations for the $h$-vector of the positive part of $\\Delta (\\Phi)$ are provided. The proof utilizes the appearance of the complex $\\Delta (\\Phi)$ in the context of the lattice $\\nc$, in recent work of two of the authors, as well as an explicit shelling of $\\Delta (\\Phi)$.", "revisions": [ { "version": "v1", "updated": "2006-02-14T09:31:19.000Z" } ], "analyses": { "subjects": [ "20F55" ], "keywords": [ "generalized associahedra", "non-crossing partitions", "finite root system", "proof utilizes", "case-free proof" ], "note": { "typesetting": "TeX", "pages": 20, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2006math......2293A" } } }