Abstract
Given n ∈ N, we consider the imprimitive wreath product C2 ≀ Sn. We study the structure of the p-modular reduction of modules whose ordinary characters form an involution model of C2 ≀ Sn, where p is an odd prime. We describe the vertices of these modules, and we use this description of the vertices to determine certain decomposition numbers of C2 ≀ Sn.
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Acknowledgements
The work in this paper was completed by the author under the supervision of Mark Wildon. The author gratefully acknowledges his support. The author also thanks Stephen Donkin and an anonymous referee for their comments on earlier versions of this paper.
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Presented by: Radha Kessar
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Kochhar, J. Vertices of Modules and Decomposition Numbers of C2 ≀ Sn. Algebr Represent Theor 23, 95–123 (2020). https://doi.org/10.1007/s10468-018-9839-8
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DOI: https://doi.org/10.1007/s10468-018-9839-8