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arXiv · 1705.00639

On codimension two flats in Fermat-type arrangements

Grzegorz Malara·Justyna Szpond
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Abstract

In the present note we study certain arrangements of codimension $2$ flats in projective spaces, we call them "Fermat arrangements". We describe algebraic properties of their defining ideals. In particular, we show that they provide counterexamples to an expected containment relation between ordinary and symbolic powers of homogeneous ideals.

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Grzegorz Malara, Justyna Szpond. 2017-05-01. On codimension two flats in Fermat-type arrangements. https://arxiv.org/abs/1705.00639

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