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Projective and generating modules over the ring of pseudorational numbers. (English. Russian original) Zbl 1137.16003
Math. Notes 80, No. 3, 417-427 (2006); translation from Mat. Zametki 80, No. 3, 437-448 (2006).
The ring of pseudorational numbers was introduced by A. A. Fomin and P. A. Krylov. In this paper some classes of modules over the ring $$R$$ of pseudorational numbers are described.
In particular, the projective $$R$$-modules are characterized and a complete independent system of invariants for projective $$R$$-modules is indicated. An $$R$$-module is flat if and only if it has nonzero elements of finite order. An $$R$$-module $$M$$ is generating if and only if $$M\cong R\oplus X$$ for some $$R$$-module $$X$$.

##### MSC:
 16D40 Free, projective, and flat modules and ideals in associative algebras 13C10 Projective and free modules and ideals in commutative rings
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##### References:
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