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arXiv · 1210.8391

A sufficient condition for F-purity

Linquan Ma
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Abstract

It is well known that nice conditions on the canonical module of a local ring have a strong impact in the study of strong F-regularity and F-purity. In this note, we prove that if (R,m) is an equidimensional and S_2 local ring that admits a canonical ideal I such that R/I is F-pure, then R is F-pure. We also provide examples to show that not all Cohen-Macaulay F-pure local rings satisfy this property.

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Linquan Ma. 2013-10-09. A sufficient condition for F-purity. https://arxiv.org/abs/1210.8391

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