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arXiv · 2006.01330

On the ubiquity of Arf rings

Ela Celikbas·Olgur Celikbas·Cătălin Ciupercă·Naoki Endo·Shiro Goto·Ryotaro Isobe·Naoyuki Matsuoka
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Abstract

We introduce and develop the theory of weakly Arf rings, which is a generalization of Arf rings, initially defined by J. Lipman in 1971. We provide characterizations of weakly Arf rings and study the relation between these rings, the Arf rings, and the strict closedness of rings. Furthermore, we give various examples of weakly Arf rings that come from idealizations, fiber products, determinantal rings, and invariant subrings.

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Ela Celikbas, Olgur Celikbas, Cătălin Ciupercă, Naoki Endo, Shiro Goto, Ryotaro Isobe, Naoyuki Matsuoka. 2020-06-02. On the ubiquity of Arf rings. https://arxiv.org/abs/2006.01330

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