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arXiv · alg-geom/9703035

The Ideal Generation Problem for Fat Points

Brian Harbourne
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Abstract

This paper is concerned with determining the number of generators in each degree for minimal sets of homogeneous generators for saturated ideals defining fat point subschemes $Z=m_1p_1+ ... +m_rp_r$ for general sets of points $p_i$ of $P^2$. For thin points (i.e., m_i=1 for all i), a solution is known, in terms of a maximal rank property. Although this property in general fails for fat points, we show it holds in an appropriate asymptotic sense. In the uniform (i.e., $m_1= ... =m_r$) case, we determine all failures of this maximal rank property for $r\le 9$, and we develop evidence for the conjecture that no other failures occur for $r > 9$.

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Brian Harbourne. 1997-03-27. The Ideal Generation Problem for Fat Points. https://arxiv.org/abs/alg-geom/9703035

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