{ "id": "1804.02761", "version": "v2", "published": "2018-04-08T21:37:07.000Z", "updated": "2019-11-01T10:59:57.000Z", "title": "Tamari Lattices for Parabolic Quotients of the Symmetric Group", "authors": [ "Henri Mühle", "Nathan Williams" ], "comment": "26 pages, 5 figures, 5 tables. Final version; added more details. Comments are welcome", "categories": [ "math.CO" ], "abstract": "We generalize the Tamari lattice by extending the notions of $231$-avoiding permutations, noncrossing set partitions, and nonnesting set partitions to parabolic quotients of the symmetric group $\\mathfrak{S}_{n}$. We show bijectively that these three objects are equinumerous. We show how to extend these constructions to parabolic quotients of any finite Coxeter group. The main ingredient is a certain aligned condition of inversion sets; a concept which can in fact be generalized to any reduced expression of any element in any (not necessarily finite) Coxeter group.", "revisions": [ { "version": "v2", "updated": "2019-11-01T10:59:57.000Z" } ], "analyses": { "subjects": [ "20F55", "06A07", "52C35" ], "keywords": [ "parabolic quotients", "tamari lattice", "symmetric group", "finite coxeter group", "noncrossing set partitions" ], "note": { "typesetting": "TeX", "pages": 26, "language": "en", "license": "arXiv", "status": "editable" } } }