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arXiv · 2210.09144

Certain endomorphism rings of local cohomology modules and Lyubeznik numbers

Alberto F. Boix·Majid Eghbali
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Abstract

The goal of this paper is twofold; on the one hand, motivated by questions raised by Schenzel, we explore situations where the Hartshorne--Lichtenbaum Vanishing Theorem for local cohomology fails, leading us to simpler expressions of certain local cohomology modules. As application, we give new expressions of the endomorphism ring of these modules. On the other hand, building upon previous work by \`Alvarez Montaner, we exhibit the shape of Lyubeznik tables of the so--called partially sequentially Cohen--Macaulay rings as introduced by Sbarra and Strazzanti.

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BibTeXRIS

Alberto F. Boix, Majid Eghbali. 2022-10-17. Certain endomorphism rings of local cohomology modules and Lyubeznik numbers. https://doi.org/10.1142/s0218196723500340

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