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arXiv · 2112.06676

Gorensteinness in Rees algebras of powers of parameter ideals

Shiro Goto·Shin-ichiro Iai
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Abstract

This paper gives a necessary and sufficient condition for Gorensteinness in Rees algebras of the $d$-th power of parameter ideals in certain Noetherian local rings of dimension $d\ge 2$. The main result of this paper produces many Gorenstein Rees algebras over non-Cohen-Macaulay local rings. For example, the Rees algebra $\mathcal{R}(\mathfrak{q}^d)=\oplus_{i\ge 0}\mathfrak{q}^{di}$ is Gorenstein for every parameter ideal $\mathfrak{q}$ that is a reduction of the maximal ideal in a $d$-dimensional Buchsbaum local ring of depth 1 and multiplicity 2.

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Shiro Goto, Shin-ichiro Iai. 2021-12-13. Gorensteinness in Rees algebras of powers of parameter ideals. https://arxiv.org/abs/2112.06676

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