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arXiv · 2009.03484

Fiber cones of rational normal scrolls are Cohen-Macaulay

Kuei-Nuan Lin·Yi-Huang Shen
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Abstract

In this short paper, we show that the fiber cones of rational normal scrolls are Cohen-Macaulay. As an application, we compute their Castelnuovo-Mumford regularities and $\mathbf{a}$-invariants, as well as the reduction number of the defining ideals of the rational normal scrolls. We also characterize the Gorensteinness of the fiber cone.

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Kuei-Nuan Lin, Yi-Huang Shen. 2021-07-12. Fiber cones of rational normal scrolls are Cohen-Macaulay. https://arxiv.org/abs/2009.03484

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