On Hilbert coefficients of parameter ideals and Cohen-Macaulayness

Kumari Saloni

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arXiv · 1609.07746

On Hilbert coefficients of parameter ideals and Cohen-Macaulayness

Kumari Saloni

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Abstract

Let $(R, \mathfrak m)$ be an unmixed Noetherian local ring, Q a parameter ideal and $K$ an $\mathfrak m$-primary ideal of $R$ containing $Q$. We give a necessary and sufficient condition for $R$ to be Cohen-Macaulay in terms of $g_0(Q)$ and $g_1(Q)$, the Hilbert coefficients of $Q$ with respect to $K$. As a consequence, we obtain a result of Ghezzi et al. which settles the negativity conjecture of W. V. Vasconcelos [15] in unmixed local rings.

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Kumari Saloni. 2016-09-25. On Hilbert coefficients of parameter ideals and Cohen-Macaulayness. https://arxiv.org/abs/1609.07746

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