Abstract
We say that a subgroup H is isolated in a group G if for every x ∈ G we have either x ∈ H or 〈x〉 ∩ H = 1. We describe the set of isolated subgroups of a finite abelian group. The technique used is based on an interesting connection between isolated subgroups and the function sum of element orders of a finite group.
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The author is grateful to the reviewer for remarks which improved the previous version of the paper.
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Tărnăuceanu, M. Isolated subgroups of finite abelian groups. Czech Math J 72, 615–620 (2022). https://doi.org/10.21136/CMJ.2022.0085-21
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DOI: https://doi.org/10.21136/CMJ.2022.0085-21