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arXiv · 2412.06218

Arithmetic in Group Extensions

Alexander Hulpke
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Abstract

We describe a generalization of the concept of a pc presentation that applies to groups with a nontrivial solvable radical. Such a representation can be much more efficient in terms of memory use and even of arithmetic, than permuattion and matrix representations. We illustrate the use of such representations by constructing a maximal subgroup of the sporadic monster group and calculating its -- hitherto unknown -- character table.

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Alexander Hulpke. 2024-12-09. Arithmetic in Group Extensions. https://doi.org/10.1016/j.jalgebra.2025.09.010

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