Necessary conditions are
given in order that Tor(A,B) be a direct sum of cyclic groups for abelian groups A
and B. Sufficient conditions are also given that compare with the necessary
conditions. They are only slightly stronger if at all, and the two are equivalent for
groups of cardinality not exceeding ℵ2.
Due to the complexity of the problem, these conditions are not absolute, but
constitute a reduction to smaller cardinality. The results generalize earlier results of
R. Nunke.
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