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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.

Keywords

Acknowledgement

Supported by : Korea Research Foundation

References

  1. R. B. J. T. Allenby, G. Kim, and C. Y. Tang, Residual finiteness of outer automorphism groups of certain pinched 1-relator groups, J. Algebra 246 (2001), no. 2, 849-858. https://doi.org/10.1006/jabr.2001.8987
  2. R. B. J. T. Allenby, G. Kim, and C. Y. Tang, Residual finiteness of outer automorphism groups of finitely generated nontriangle Fuchsian groups, Internat. J. Algebra Comput. 15 (2005), no. 1, 59-72. https://doi.org/10.1142/S0218196705002104
  3. W. Burnside, On the outer automorphisms of a group, Proc. London Math. Soc. 11 (1913), 40-42. https://doi.org/10.1112/plms/s2-11.1.40
  4. J. L. Dyer, Separating conjugates in amalgamated free products and HNN extensions, J. Austral. Math. Soc. Ser. A 29 (1980), no. 1, 35-51. https://doi.org/10.1017/S1446788700020917
  5. G. Endimioni, Pointwise inner automorphisms in a free nilpotent group, Q. J. Math. 53 (2002), no. 4, 397-402. https://doi.org/10.1093/qjmath/53.4.397
  6. E. K. Grossman, On the residual finiteness of certain mapping class groups, J. London Math. Soc. (2) 9 (1974), 160-164. https://doi.org/10.1112/jlms/s2-9.1.160
  7. S. Jackowski and Z. Marciniak, Group automorphisms inducing the identity map on cohomology, J. Pure Appl. Algebra 44 (1987), no. 1-3, 241-250. https://doi.org/10.1016/0022-4049(87)90028-4
  8. W. Magnus, A. Karrass, and D. Solitar, Combinatorial Group Theory, Pure and Applied Math. Vol. XIII, Wiley-Interscience, New York-London-Sydney, 1966.
  9. M. V. Neshadim, Free products of groups that do not have outer normal automorphisms, Algebra and Logic 35 (1996), no. 5, 316-318. https://doi.org/10.1007/BF02367356
  10. D. Segal, On the outer automorphism group of a polycyclic group, In Proc. of the Second International Group Theory Conference (Bressanone, 1989), Rend. Circ. Mat. Palermo (2) Suppl. No. 23 (1990), 265-278.
  11. G. E. Wall, Finite groups with class-preserving outer automorphisms, J. London Math. Soc. 22 (1947), 315-320. https://doi.org/10.1112/jlms/s1-22.4.315
  12. P. C. Wong and K. B. Wong, Residual finiteness of outer automorphism groups of certain tree products, J. Group Theory 10 (2007), no. 3, 389-400.
  13. W. Zhou and G. Kim, Class-preserving automorphisms and inner automorphisms of certain tree products of groups, J. Algebra 341 (2011), 198-208. https://doi.org/10.1016/j.jalgebra.2011.05.036

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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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