{ "id": "1211.4305", "version": "v1", "published": "2012-11-19T05:28:46.000Z", "updated": "2012-11-19T05:28:46.000Z", "title": "Inequalities on Bruhat graphs, R- and Kazhdan-Lusztig polynomials", "authors": [ "Masato Kobayashi" ], "comment": "16 pages", "journal": "Journal of Combinatorial Series A 120 (2013) no.2, 470--482", "categories": [ "math.CO" ], "abstract": "From a combinatorial perspective, we establish three inequalities on coefficients of $R$- and Kazhdan-Lusztig polynomials for crystallographic Coxeter groups: (1) Nonnegativity of $(q-1)$-coefficients of $R$-polynomials, (2) a new criterion of rational singularities of Bruhat intervals by sum of quadratic coefficients of $R$-polynomials, (3) existence of a certain strict inequality (coefficientwise) of Kazhdan-Lusztig polynomials. Our main idea is to understand Deodhar's inequality in a connection with a sum of $R$-polynomials and edges of Bruhat graphs.", "revisions": [ { "version": "v1", "updated": "2012-11-19T05:28:46.000Z" } ], "analyses": { "subjects": [ "20F55", "51F15" ], "keywords": [ "kazhdan-lusztig polynomials", "bruhat graphs", "understand deodhars inequality", "crystallographic coxeter groups", "bruhat intervals" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 16, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1211.4305K" } } }