A GENERALIZATION OF HAJOS’ THEOREM

A GENERALIZATION OF HAJOS’ THEOREM

Haj´os’ Theorem states that if a finite abelian group is expressed as a direct product of cyclic subsets, then one of these subsets must be a subgroup. Here factorizations are considered in which one of the factors is not assumed to be cyclic but has certain restrictions on its order placed upon it.

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  • Department of Mathematics Dundee University
  • Dundee DD1 4HN Scotland
  • E-mail: adsands@maths.dundee.ac.uk