Abstract
In this paper we show that the leading coefficient µ(y,w) of some Kazhdan-Lusztig polynomials P y,w with y,w in an affine Weyl group of type à n is n + 2. This fact has some consequences on the dimension of first extension groups of finite groups of Lie type with irreducible coefficients.
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Scott, L., Xi, N. Some non-trivial Kazhdan-Lusztig coefficients of an affine Weyl group of type à n . Sci. China Math. 53, 1919–1930 (2010). https://doi.org/10.1007/s11425-010-4041-4
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DOI: https://doi.org/10.1007/s11425-010-4041-4