A new approach to a theorem of Eng

Year 2021, Volume: 50 Issue: 6, 1679 - 1680, 14.12.2021

Hasan Arslan

https://doi.org/10.15672/hujms.900705

Abstract

The main aim of this work is to give a case-free algebraic proof for a theorem of Eng on the Poincaré polynomial of parabolic quotients of finite Coxeter groups evaluated at -1.

Keywords

Coxeter groups , descent algebras , Poincaré polynomial , the longest element , $q=-1$ phenomenon

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