【摘 要】
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For a semi-projective retractable module MR with endomorphism ring S,we prove u.dim MR = u.dim Ss,and find necessary and sufficient conditions on M in order tha
【机 构】
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Department of Mathematics,Isfahan University of Technology,Isfahan,Iran
论文部分内容阅读
For a semi-projective retractable module MR with endomorphism ring S,we prove u.dim MR = u.dim Ss,and find necessary and sufficient conditions on M in order that S be respectively semiprime,right nonsingular,finitely cogenerated,cocyclic,or weakly co-Hopfian.Precise descriptions of the right singular ideal of S and the socle of M are given,and in addition if S is a semiprime ring,it is shown that MR is FI-extending if and only if Ss is FI-extending.
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