More Abelian Groups with Free Duals

نویسنده

  • GEORGE M. BERGMAN
چکیده

In answer to a question of A. Blass, J. Irwin and G. Schlitt, a subgroup G of the additive group Zω is constructed whose dual, Hom(G,Z), is free abelian of rank 2א0 . The question of whether Zω has subgroups whose duals are free of still higher rank is discussed, and some further classes of subgroups of Zω are noted.

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تاریخ انتشار 2012