The intersection of the subgroups of finite $p$-index in a multiple HNN-extension of an infinite cyclic group

V. Metaftsis; D. Tsipa

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arXiv · 2504.21542

The intersection of the subgroups of finite $p$-index in a multiple HNN-extension of an infinite cyclic group

V. Metaftsis·D. Tsipa

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Abstract

Let $G$ be a multiple HNN-extension of an infinite cyclic group. We will calculate the intersection $(N_{p}){_\omega}(G)$ of the normal subgroups of finite $p$-index in $G$ thus generalizing the result of Moldavanskii for Baumslag-Solitar groups. As a corollary we give necessary and sufficient conditions for $G$ to be residually finite $p$-group.

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BibTeX RIS

V. Metaftsis, D. Tsipa. 2025-04-30. The intersection of the subgroups of finite $p$-index in a multiple HNN-extension of an infinite cyclic group. https://arxiv.org/abs/2504.21542

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