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arXiv · 1407.0168

Syzygies of Jacobian ideals and weighted homogeneous singularities

Alexandru Dimca·Gabriel Sticlaru
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Abstract

Let $V$ be a projective hypersurface having only isolated singularities. We show that these singularities are weighted homogeneous if and only if the Koszul syzygies among the partial derivatives of an equation for $V$ are exactly the syzygies with a generic first component vanishing on the singular locus subscheme of $V$. This yields in particular a positive answer in this setting to a question raised by Morihiko Saito and the first author. Finally we explain how our result can be used to improve the listing of Jacobian syzygies of a given degree by a computer algebra system such as Singular, CoCoA or Macaulay2.

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Alexandru Dimca, Gabriel Sticlaru. 2014-07-01. Syzygies of Jacobian ideals and weighted homogeneous singularities. https://arxiv.org/abs/1407.0168

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