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no. 5
Decomposition numbers for weight $3$ blocks of Iwahori–Hecke algebras of type $B$
Fayers, Matthew1; Putignano, Lorenzo2
1 Queen Mary University of London
2 Università degli Studi di Firenze
Algebraic Combinatorics, Volume 8 (2025) no. 5, pp. 1251-1284

Let $B$ be a weight-$3$ block of an Iwahori–Hecke algebra of type $B$ over any field. We develop the combinatorics of $B$ to prove that the decomposition numbers for $B$ are all $0$ or $1$.

Received:
Revised:
Accepted:
Published online:
DOI: 10.5802/alco.446
Classification: 20C08, 20C30, 05E10
Keywords: Iwahori-Hecke algebra, decomposition numbers, Specht modules

Fayers, Matthew 1; Putignano, Lorenzo 2

1 Queen Mary University of London
2 Università degli Studi di Firenze
License: CC-BY 4.0
Copyrights: The authors retain unrestricted copyrights and publishing rights 
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Fayers, Matthew; Putignano, Lorenzo. Decomposition numbers for weight $3$ blocks of Iwahori–Hecke algebras of type $B$. Algebraic Combinatorics, Volume 8 (2025) no. 5, pp. 1251-1284. doi: 10.5802/alco.446

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