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Licensed Unlicensed Requires Authentication Published by De Gruyter September 21, 2021

Isomorphism classification of Leary–Minasyan groups

  • Motiejus Valiunas EMAIL logo
From the journal Journal of Group Theory


Recently, I. J. Leary and A. Minasyan [Commensurating HNN extensions: Nonpositive curvature and biautomaticity, Geom. Topol. 25 (2021), 4, 1819–1860] studied the class of groups G ( A , L ) defined as commensurating HNN-extensions of Z n . This class, containing the class of Baumslag–Solitar groups, also includes other groups with curious properties, such as being CAT(0) but not biautomatic. In this paper, we classify the groups G ( A , L ) up to isomorphism.


The author wishes to thank Ian Leary and Ashot Minasyan for useful comments, and the referee for their careful reading of the paper and valuable feedback.

  1. Communicated by: Alexander Olshanskii


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Received: 2021-03-10
Revised: 2021-08-05
Published Online: 2021-09-21
Published in Print: 2022-03-01

© 2021 Walter de Gruyter GmbH, Berlin/Boston

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