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arXiv · 2306.04267

The blocks with five irreducible characters

J. Miquel Martínez·Noelia Rizo·Lucia Sanus
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Abstract

Let $G$ be a finite group, $p$ a prime and $B$ a Brauer $p$-block of $G$ with defect group $D$. We prove that if the number of irreducible ordinary characters in $B$ is $5$ then $D\cong C_5, C_7, D_8$ or $Q_8$, assuming that the Alperin--McKay conjecture holds for $B$.

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J. Miquel Martínez, Noelia Rizo, Lucia Sanus. 2023-06-07. The blocks with five irreducible characters. https://arxiv.org/abs/2306.04267

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