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arXiv · 2603.25407

Groups with a conjugacy class that is the difference of two normal subgroups

Mark L. Lewis·Lucia Morotti·Emanuele Pacifici·Lucia Sanus·Hung P. Tong-Viet
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Abstract

We consider finite groups having a conjugacy class that is the difference of two normal subgroups. That is, suppose $G$ is a group and $M$ and $N$ are normal subgroups so that $N < M$, and suppose that there is an element $g \in G$ so that the conjugacy class of $g$ is $M \setminus N$. We find a character-theoretic characterization of this condition, and we determine some structural properties of groups with such a conjugacy class. If we add the condition that $M/N$ is the unique minimal normal subgroup of $G/N$, then we obtain a generalization of a result by S.M. Gagola.

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Mark L. Lewis, Lucia Morotti, Emanuele Pacifici, Lucia Sanus, Hung P. Tong-Viet. 2026-03-26. Groups with a conjugacy class that is the difference of two normal subgroups. https://arxiv.org/abs/2603.25407

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