Quasi-pure projective and injective torsion free abelian groups of rank 2
نویسندگان
چکیده
منابع مشابه
On the Classification Problem for Rank 2 Torsion-free Abelian Groups
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...
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In 1937, Baer solved the classification problem for the torsion-free abelian groups of rank 1. Since then, despite the efforts of many mathematicians, no satisfactory solution has been found of the classification problem for the torsion-free abelian groups of rank n ≥ 2. So it is natural to ask whether the classification problem for the higher rank groups is genuinely difficult. In this article...
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ژورنال
عنوان ژورنال: Rocky Mountain Journal of Mathematics
سال: 1976
ISSN: 0035-7596
DOI: 10.1216/rmj-1976-6-1-61