Arkiv för Matematik

, Volume 10, Issue 1–2, pp 231–234 | Cite as

The direct product of a hopfian group with a group with cyclic ccnter

  • R. Hirshon


In this paper we continue our study of hopficity begun in [1], [2], [3], [4] and [5]. LetA be hopfian and letB have a cyclic center of prime power order. We improve Theorem 4 of [2] by showing that ifB has finitely many normal subgroups which form a chain (we sayB isn-normal), thenAxB is hopfian. We then consider the case whenB is ap-group of nilpotency class 2 and show that in certain casesAxB is hopfian.


Abelian Group Normal Subgroup Direct Product Related Result Polytechnic Institute 
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Copyright information

© Institut Mittag-Leffler 1972

Authors and Affiliations

  • R. Hirshon
    • 1
  1. 1.Polytechnie Institute of BrooklynBrooklynU.S.A.

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