NEW CRITERIA FOR FREENESS IN ABELIAN GROUPS . H ( i )
نویسنده
چکیده
A new criterion is established for an abelian group to be free. The criterion is in terms of an ascending chain of free subgroups and is dependent upon a new class of torsion-free groups. The result leads to the construction, for each positive integer n, of a group G of cardinality K that is not free but is X -free. A conjecture in infinitary logic concern71 n ing free abelian groups is also verified.
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