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arXiv · 1511.04073

Equations of Rees algebras of ideals in two variables

Jeff Madsen
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Abstract

Let I be an ideal of height two in R=k[x_0,x_1] generated by forms of the same degree, and let K be the ideal of defining equations of the Rees algebra of I. Suppose that the second largest column degree in the syzygy matrix of I is e. We give an algorithm for computing the minimal generators of K whose degree is at least e, as well as a simple formula for the bidegrees of these generators. In the case where I is an almost complete intersection, we give a generating set for each graded piece K_(i,*) with i>=e-1.

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Jeff Madsen. 2015-11-12. Equations of Rees algebras of ideals in two variables. https://arxiv.org/abs/1511.04073

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