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CLASS-PRESERVING AUTOMORPHISMS OF GENERALIZED FREE PRODUCTS AMALGAMATING A CYCLIC NORMAL SUBGROUP

  • Zhou, Wei (School of Mathematics and Statistics Southwest University) ;
  • Kim, Goan-Su (Department of Mathematics Yeungnam University)
  • Received : 2011.05.11
  • Published : 2012.09.30

Abstract

In general, a class-preserving automorphism of generalized free products of nilpotent groups, amalgamating a cyclic normal subgroup of order 8, need not be an inner automorphism. We prove that every class-preserving automorphism of generalized free products of nitely generated nilpotent groups, amalgamating a cyclic normal subgroup of order less than 8, is inner.

Acknowledgement

Supported by : Korea Research Foundation

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  2. Class-preserving automorphisms of certain HNN extensions vol.431, 2015, https://doi.org/10.1016/j.jalgebra.2015.02.012
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