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arXiv · 2508.02306

On the isomorphism problem for generalized Baumslag-Solitar groups: invariants and flexible configurations

Dario Ascari·Montserrat Casals-Ruiz·Ilya Kazachkov
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Abstract

We prove that the isomorphism problem is decidable for generalized Baumslag-Solitar (GBS) groups with one quasi-conjugacy class and full support gaps. In order to do so we introduce a family of invariants that fully characterize the isomorphism within this class of GBSs.

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Dario Ascari, Montserrat Casals-Ruiz, Ilya Kazachkov. 2025-08-04. On the isomorphism problem for generalized Baumslag-Solitar groups: invariants and flexible configurations. https://arxiv.org/abs/2508.02306

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