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arXiv · 1804.07558

Cohomology of ideals in elliptic surface singularities

Tomohiro Okuma
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Abstract

We introduce the the normal reduction number of two-dimensional normal singularities and prove that elliptic singularity has normal reduction number two. We also prove that for a two-dimensional normal singularity which is not rational, it is Gorenstein and its maximal ideal is a $p_g$-ideal if and only if it is a maximally elliptic singularity of degree $1$.

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Tomohiro Okuma. 2018-04-20. Cohomology of ideals in elliptic surface singularities. https://doi.org/10.1215/ijm/1534924827

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