Kezlan, Thomas P. A commutativity theorem involving certain polynomial constraints. (English) Zbl 0735.16021 Math. Jap. 36, No. 4, 785-789 (1991). It is shown that if \(n\) is a positive integer and \(R\) is an associative ring with unity, having the property: (*) given \(x,y\) in \(R\) there exists an integer \(m=m(x,y)>1\) such that \([xy-y^ mx^ n,x]=0\) then \(R\) must be commutative. If we consider \(m\) independent of \(x\) and \(y\), we obtain a theorem which has been proved by M. A. Quadri and M. Khan [Math. Jap. 33, 275-279 (1988; Zbl 0655.16021)]. The case in which both \(m\) and \(n\) are allowed to depend on \(x\) and \(y\) remains open. Reviewer: M.Guţan Cited in 1 ReviewCited in 2 Documents MSC: 16U70 Center, normalizer (invariant elements) (associative rings and algebras) 16U80 Generalizations of commutativity (associative rings and algebras) Keywords:commutativity; polynomial constraints Citations:Zbl 0655.16021 PDFBibTeX XMLCite \textit{T. P. Kezlan}, Math. Japon. 36, No. 4, 785--789 (1991; Zbl 0735.16021)