Publication Title

Communications in Algebra

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Department or Program


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free product of groups, three-manifolds, Twisted conjugacy


Let (Formula presented.) be an automorphism of a group which is a free product of finitely many groups each of which is freely indecomposable and two of the factors contain proper finite index characteristic subgroups. We show that G has infinitely many (Formula presented.) -twisted conjugacy classes. As an application, we show that if G is the fundamental group of a three-manifold that is not irreducible, then G has property (Formula presented.) that is, there are infinitely many (Formula presented.) -twisted conjugacy classes in G for every automorphism (Formula presented.) of G.

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This is the author's version of the work. This publication appears in Bates College's institutional repository by permission of the copyright owner for personal use, not for redistribution.

Required Publisher's Statement

This is an Accepted Manuscript of an article published by Taylor & Francis in Communications in Algebra on 25 Mar 2020, available at: