Groups with many normal-by-finite subgroups

Franciosi, Silvana; de Giovanni, Francesco

doi:10.1090/S0002-9939-97-03539-9

Groups with many normal-by-finite subgroups
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by Silvana Franciosi and Francesco de Giovanni

Proc. Amer. Math. Soc. 125 (1997), 323-327

DOI: https://doi.org/10.1090/S0002-9939-97-03539-9

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Abstract:

A subgroup $H$ of a group $G$ is said to be normal-by-finite if the core $H_G$ of $H$ in $G$ has finite index in $H$. In this article groups satisfying the minimal condition on subgroups which are not normal-by-finite and groups with finitely many conjugacy classes of subgroups which are not normal-by-finite are characterized.

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