On the non-existence of finite groups with certain normal subgroups

Ihechukwu Chinyere

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arXiv · 2601.01080

On the non-existence of finite groups with certain normal subgroups

Ihechukwu Chinyere

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Abstract

Problem 20.21 of Mazurov and Khukhro (Unsolved Problems in Group Theory: The Kourovka Notebook, 20th Issue, 2022), contributed by M.~Conder and attributed to G.~Verret, asks whether there exists a finite group $G$ with two normal subgroups $K$ and $L$ of index $12$ such that $K \cong L$, but with non-isomorphic quotients $G/K \cong C_{12}$ and $G/L \cong A_4.$ We prove that no such finite group exists.

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Ihechukwu Chinyere. 2026-01-07. On the non-existence of finite groups with certain normal subgroups. https://arxiv.org/abs/2601.01080

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