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arXiv · 2109.10654

The blocks with four irreducible characters

J. Miquel Martínez·Noelia Rizo·Lucía Sanus
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Abstract

Suppose that $B$ is a Brauer $p$-block with defect group $D$. If $B$ exactly contains 4 irreducible characters, then we show that $D$ has order 4 or 5, assuming the Alperin--McKay conjecture.

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J. Miquel Martínez, Noelia Rizo, Lucía Sanus. 2021-09-22. The blocks with four irreducible characters. https://arxiv.org/abs/2109.10654

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