Poincaré series of subsets of affine Weyl groups

Viswanath, Sankaran

doi:10.1090/S0002-9939-08-09382-9

Poincaré series of subsets of affine Weyl groups
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Proc. Amer. Math. Soc. 136 (2008), 3735-3740 Request permission

Abstract:

In this note, we identify a natural class of subsets of affine Weyl groups whose Poincaré series are rational functions. This class includes the sets of minimal coset representatives of reflection subgroups. As an application, we construct a generalization of the classical length-descent generating function and prove its rationality.

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