SOME RESULTS ON COFINITE MODULES

Abstract

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.

Keywords

• Auslander-Buchsbaum formula, Bass formula, local cohomology, cofinite module

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29. Department of Mathematics Faculty of Science Shahrekord University Shahrekord, Iran e-mail: [e-mail]