Disjoint Non-free Subgoups of Abelian Groups

نویسندگان

  • ANDREAS BLASS
  • John Irwin
چکیده

Let G be an abelian group and let λ be the smallest rank of any group whose direct sum with a free group is isomorphic to G. If λ is uncountable, then G has λ pairwise disjoint, non-free subgroups. There is an example where λ is countably infinite and G does not have even two disjoint, non-free subgroups.

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تاریخ انتشار 2005