SOME RESULTS ON COFINITE MODULES

Let R be a Noetherian ring and a be a proper ideal of R. We generalize the Rees characterization of grade for a-cofinite modules and as a consequence, we extend Grothendieck’s Non-vanishing Theorem. We also generalize the classical Auslander-Buchsbaum and Bass formulas.

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  • Department of Mathematics Faculty of Science Shahrekord University Shahrekord, Iran e-mail: naghipour@sci.sku.ac.ir