A new approach to a theorem of Eng

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

References

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