caa a22 4500 467997470 CHVBK 20180323112600.0 cr unu---uuuuu 170328e19901001xx s 000 0 eng 10.1007/BF00181467 doi (NATIONALLICENCE)springer-10.1007/BF00181467 Deodhar Vinay Department of Mathematics, Indiana University, 47405, Bloomington, IN, USA aut A combinatorial setting for questions in Kazhdan — Lusztig theory [Elektronische Daten] [Vinay Deodhar] Let(W, S) be a Coxeter group. Let s 1 ... s k be a reduced expression for an element y in W. A combinatorial setting involving subexpressions of this reduced expression is developed. This leads to the notion of good elements. It is proved that all elements in a group where the coefficients of Kazhdan — Lusztig polynomials are non-negative are good. If y is good then an algorithm is developed to compute these polynomials in a very efficient way. It is further proved that in these cases, the coefficients of these polynomials can be identified as sizes of certain subsets of subexpressions thereby providing an explicit setting for various questions regarding these polynomials and related topics. Similar results are obtained for the so-called parabolic case. Kluwer Academic Publishers, 1990 Geometriae Dedicata Kluwer Academic Publishers 36/1(1990-10-01), 95-119 0046-5755 36:1<95 1990 36 10711 https://doi.org/10.1007/BF00181467 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00181467 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Deodhar Vinay Department of Mathematics, Indiana University, 47405, Bloomington, IN, USA aut NATIONALLICENCE 773 0- Geometriae Dedicata Kluwer Academic Publishers 36/1(1990-10-01), 95-119 0046-5755 36:1<95 1990 36 10711 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer