A free product of finitely generated nilpotent groups amalgamating a cycle that is not subgroup separable

Allenby, R.; Doniz, David

doi:10.1090/S0002-9939-96-03567-8

A free product of finitely generated nilpotent groups amalgamating a cycle that is not subgroup separable
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by R. B. J. T. Allenby and David Doniz PDF

Proc. Amer. Math. Soc. 124 (1996), 1003-1005 Request permission

Abstract:

We exhibit a counterexample to a recent assertion concerning the subgroup separability of groups in the title. The example also serves as a simplification of work of Gitik and Rips.

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