Startseite Computation of endo-fixed closures in free-abelian times free groups
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Computation of endo-fixed closures in free-abelian times free groups

  • Mallika Roy ORCID logo EMAIL logo und Enric Ventura
Veröffentlicht/Copyright: 10. Februar 2025

Abstract

In this paper, we explore the behaviour of the fixed subgroups of endomorphisms of free-abelian times free (FATF) groups. We exhibit an algorithm which, given a finitely generated subgroup of a FATF group 𝒢 , decides whether is the fixed subgroup of some (finite) family of endomorphisms of 𝒢 and, in the affirmative case, finds such a family. The algorithm combines both combinatorial and algebraic methods.

MSC 2020: 20E05; 20E36; 20K15

Communicated by Clara Löh


Funding statement: The authors acknowledge support from the Spanish Agencia Estatal de Investigación through grant PID2021-126851NB-100 (AEI/ FEDER, UE). The first named author wants to thank the hospitality received from Universidad del País Vasco, and support through a Margarita Salas grant from Universitat Politècnica de Catalunya.

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Received: 2023-12-21
Revised: 2024-12-18
Published Online: 2025-02-10
Published in Print: 2025-06-01

© 2025 Walter de Gruyter GmbH, Berlin/Boston

Heruntergeladen am 19.9.2025 von https://www.degruyterbrill.com/document/doi/10.1515/forum-2023-0471/html
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