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arXiv · 2409.17551

On the ordinary and symbolic powers of fiber products

Hoang Viet Do·Hop D. Nguyen·Seyed Amin Seyed Fakhari
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Abstract

We completely determine the depth and regularity of symbolic powers of the fiber product of two homogeneous ideals in disjoint sets of variables, given knowledge of the symbolic powers of each factor. Generalizing previous joint work with Vu, we provide exact, characteristic-independent formulas for the depth and regularity of ordinary powers of such fiber products.

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Hoang Viet Do, Hop D. Nguyen, Seyed Amin Seyed Fakhari. 2024-09-26. On the ordinary and symbolic powers of fiber products. https://arxiv.org/abs/2409.17551

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