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arXiv · 0704.0581

Counting characters in linear group actions

Thomas Michael Keller
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Abstract

Let $G$ be a finite group and $V$ be a finite $G$--module. We present upper bounds for the cardinalities of certain subsets of $\Irr(GV)$, such as the set of those $χ\in\Irr(GV)$ such that, for a fixed $v\in V$, the restriction of $χ$ to $ $ is not a multiple of the regular character of $ $. These results might be useful in attacking the non--coprime $k(GV)$--problem.

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Thomas Michael Keller. 2007-04-04. Counting characters in linear group actions. https://arxiv.org/abs/0704.0581

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