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Semistability of amalgamated products, HNN-extensions, and all one-relator groups

Michael L. Mihalik·Steven T. Tschantz
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Abstract

The authors announce the following theorem. Theorem 1. If $G=A*_H B$ is an amalgamated product where $A$ and $B$ are finitely presented and semistable at infinity, and $H$ is finitely generated, then $G$ is semistable at infinity. If $G=A*_H$ is an HNN-extension where $A$ is finitely presented and semistable at infinity, and $H$ is finitely generated, then $G$ is semistable at infinity.

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Michael L. Mihalik, Steven T. Tschantz. 1992-01-01. Semistability of amalgamated products, HNN-extensions, and all one-relator groups. https://arxiv.org/abs/math/9201264

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