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arXiv · 0909.3394

Some Non-Trivial Kazhdan-Lusztig Coefficients of an Affine Weyl Group of Type $\tilde A_n$

Leonard Scott·Nanhua Xi
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Abstract

In this paper we show that the leading coefficient $\mu(y,w)$ of some Kazhdan-Lusztig polynomials $P_{y,w}$ with $y,w$ in an affine Weyl group of type $\tilde A_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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BibTeXRIS

Leonard Scott, Nanhua Xi. 2009-09-18. Some Non-Trivial Kazhdan-Lusztig Coefficients of an Affine Weyl Group of Type $\tilde A_n$. https://doi.org/10.1007/s11425-010-4041-4

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