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arXiv · 2502.01917

Blowup Algebras of $n$--dimensional Ferrers Diagrams

Kuei-Nuan Lin·Yi-Huang Shen
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Abstract

We demonstrate that the direct sum of ideals satisfying the strong $\ell$-exchange property is of fiber type. Furthermore, we provide Gr\"obner bases of the presentation ideals of multi-Rees algebras and the corresponding special fibers, when they are associated with an $n$-dimensional Ferrers diagram that is standardizable. In particular, we show that these blowup algebras are Koszul Cohen--Macaulay normal domains and classify their singularities.

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Kuei-Nuan Lin, Yi-Huang Shen. 2025-02-04. Blowup Algebras of $n$--dimensional Ferrers Diagrams. https://arxiv.org/abs/2502.01917

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