Document Type : Research Paper


Department of Mathematics, University of Zanjan University Blvd., 45371-38791, Zanjan.


The asymptotic behaviour of the sequence with general term $P_n=(\varphi(1)+\varphi(2)+\cdots+\varphi(n))/(1+2+\cdots+n)$, is studied which appears in the studying of coprime integers, and an explicit bound for the difference $P_n-6/\pi^2$ is found.


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