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arXiv · 1707.07302

On the number of generators of powers of an ideal

Jürgen Herzog·Maryam Mohammadei Saem·Naser Zamani
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Abstract

We study the number of generators of ideals in regular rings and ask the question whether $\mu(I)<\mu(I^2)$ if $I$ is not a principal ideal, where $\mu(J)$ denotes the number of generators of an ideal $J$. We provide lower bounds for the number of generators for the powers of an ideal and also show that the CM-type of $I^2$ is $\geq 3$ if $I$ is a monomial ideal of height $n$ in $K[x_1,\ldots,x_n]$ and $n\geq 3$.

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Jürgen Herzog, Maryam Mohammadei Saem, Naser Zamani. 2017-07-23. On the number of generators of powers of an ideal. https://arxiv.org/abs/1707.07302

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