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arXiv · 2201.03927

Melkersson condition for extension of Serre subcategories

Ismael Akray·Runak H. Mustafa·Reza Sazeedeh
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Abstract

Let $R$ be a commutative noetherian ring and let $\frak a$ be an ideal of $R$. In this paper, we study a certain condition, namely $C_{\frak a}$, introduced by Aghapournahr and Melkersson, on the extension of two subcategories of $R$-modules. We extend and generalize some of the main results of Yoshizawa [Y1,Y2]. As an example of extension of subcategories, we study the weakly Laskerian modules and we find some conditions under which the local cohomology modules of a weakly Laskerian module lie in an arbitrary Serre subcategory. Eventually, we investigate the cofiniteness of the local cohomology modules of weakly Laskerian modules.

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Ismael Akray, Runak H. Mustafa, Reza Sazeedeh. 2022-01-11. Melkersson condition for extension of Serre subcategories. https://arxiv.org/abs/2201.03927

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