Balanced subgroups of finite rank completely decomposable abelian groups

Author:
Loyiso G. Nongxa

Journal:
Trans. Amer. Math. Soc. **301** (1987), 637-648

MSC:
Primary 20K15

MathSciNet review:
882707

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Abstract: It is proved that, if a finite rank completely decomposable group has extractable typeset of cardinality at most 5, all its balanced subgroups are also completely decomposable. Balanced Butler groups with extractable typeset of size at most 3 are almost completely decomposable and decompose into rank 1 and/or rank 3 indecomposable summands. We also construct an indecomposable balanced Butler group whose extractable typeset is of size 4 which fails to be almost completely decomposable.

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DOI:
https://doi.org/10.1090/S0002-9947-1987-0882707-3

Article copyright:
© Copyright 1987
American Mathematical Society