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arXiv · 1308.2170

Graded decomposition numbers of Ariki-Koike algebras for blocks of small weight

Sinead Lyle·Oliver Ruff
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Abstract

We present some blocks of Ariki-Koike algebras $\mathcal{H}_{n,r}$ for which the decomposition matrices are independent of the characteristic of the underlying field. We complete the description of the graded decomposition numbers for blocks of Ariki-Koike algebras of weight at most two, which consists of analysing the indecomposable core blocks at level $r = 3$, and give a closed formula for the decomposition numbers in this case.

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Sinead Lyle, Oliver Ruff. 2013-08-09. Graded decomposition numbers of Ariki-Koike algebras for blocks of small weight. https://arxiv.org/abs/1308.2170

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