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arXiv · 1301.0743

Covering monolithic groups with proper subgroups

Martino Garonzi
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Abstract

Given a finite non-cyclic group $G$, call $σ(G)$ the smallest number of proper subgroups of $G$ needed to cover $G$. Lucchini and Detomi conjectured that if a nonabelian group $G$ is such that $σ(G) < σ(G/N)$ for every non-trivial normal subgroup $N$ of $G$ then $G$ is \textit{monolithic}, meaning that it admits a unique minimal normal subgroup. In this paper we show how this conjecture can be attacked by the direct study of monolithic groups.

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Martino Garonzi. 2013-01-04. Covering monolithic groups with proper subgroups. https://arxiv.org/abs/1301.0743

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