^{}Department of Mathematics, Islamic Azad University, Central Tehran Branch, PO. Code 14168-94351, Iran

Abstract

A ring R is uniquely (nil) clean in case for any $a \in R$ there exists a uniquely idempotent $e\in R$ such that $a-e$ is invertible (nilpotent). Let $C =(A V W B)$ be the Morita Context ring. We determine conditions under which the rings $A,B$ are uniquely (nil) clean. Moreover we show that the center of a uniquely (nil) clean ring is uniquely (nil) clean.

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