On the Classification Problem for Rank 2 Torsion-free Abelian Groups
نویسنده
چکیده
We study here some foundational aspects of the classification problem for torsionfree abelian groups of finite rank. These are, up to isomorphism, the subgroups of the additive groups (1n,), for some n ̄ 1, 2, 3,... . The torsion-free abelian groups of rank% n are the subgroups of (1n,). For n ̄ 1, that is, the subgroups of (1,), the isomorphism problem was solved by Baer in the 1930s (see [10]). For every torsion-free abelian group G, x `G, x1 0, and p `P ̄ the set of primes, let
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تاریخ انتشار 2000