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WHEN IS AN ENDOMORPHISM RING P-COHERENT?

  • Mao, Lixin (INSTITUTE OF MATHEMATICS NANJING INSTITUTE OF TECHNOLOGY)
  • Published : 2009.01.31

Abstract

A ring is called left P-coherent if every principal left ideal is finitely presented. Let M be a right R-module with the endomorphism ring S. We mainly study the P-coherence of S. It is shown that S is a left P-coherent ring if and only if the left annihilator $ann_S$(X) is a finitely generated left ideal of S for any M-cyclic submodule X of M if and only if every cyclically M-presented right R-module has an M-torsionfree preenvelope. As applications, we investigate when the endomorphism ring S is left PP or von Neumann regular.

Keywords

References

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