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arXiv · 2608.22581

Cosyzygy modules

Petter Andreas Bergh·David A. Jorgensen·Peder Thompson
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Abstract

We characterize all first cosyzygy modules of a given finitely generated module over a local ring. We do this by introducing the notion of a canonical cosyzygy module, and showing how other cosyzygy modules can be obtained from this module. As an application, we characterize Gorenstein rings via properties of canonical first cosyzygy modules.

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Petter Andreas Bergh, David A. Jorgensen, Peder Thompson. 2026-08-23. Cosyzygy modules. https://arxiv.org/abs/2608.22581

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