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arXiv · 2307.16237

Rings whose Nil-Clean and Clean Elements are Uniquely Nil-Clean

Jian Cui·Peter Danchev·Danya-Jin
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Abstract

We consider and study those rings in which each nil-clean or clean element is uniquely nil-clean. We establish that, for abelian rings, these rings have a satisfactory description and even it is shown that the classes of abelian rings and the rings in which nil-clean elements are uniquely nil-clean do coincide. Moreover, we prove that the rings in which clean elements are uniquely nil-clean coincide with the subclass of abelian rings consisting of only unipotent units and, in particular, that in the semipotent case we have a complete characterization only in terms of the former ring and its divisions. Likewise, some extension properties and group rings for such kinds of rings are also considered.

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Jian Cui, Peter Danchev, Danya-Jin. 2023-07-30. Rings whose Nil-Clean and Clean Elements are Uniquely Nil-Clean. https://arxiv.org/abs/2307.16237

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