A brief journey through extensions of rational groups
نویسنده
چکیده
Let A and B be rational groups, i.e. torsion-free groups of rank-1 and thus subgroups of the rational numbers. This paper gives a short overview of the structure of Ext(A,B) especially considering some interesting classes of torsion-free pairs. Mathematics Subject Classification (2010). 20K15, 20K35.
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