Decomposition numbers for the principal Φ_2n-block of Sp_4n(q) and SO_4n+1(q)

2021/02/11 by Olivier Dudas, Dudas, Olivier, Emily Norton +1
Mathematics · #Advanced Algebra and Geometry #Finite Group Theory Research #Algebraic structures and combinatorial models

paper · pdf · doi:10.48550/arxiv.2102.06055

Abstract

We compute the decomposition numbers of the unipotent characters lying in the principal ℓ-block of a finite group of Lie type B_2n(q) or C_2n(q) when q is an odd prime power and ℓ is an odd prime number such that the order of q mod ℓ is 2n. Along the way, we extend to these finite groups the results of \citeDVV19 on the branching graph for Harish-Chandra induction and restriction.

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