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arXiv · 0902.2520

Two new proofs of the complete monotonicity of a function involving the psi function

Feng Qi·Bai-Ni Guo
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Abstract

In the present paper, we give two new proofs for the necessary and sufficient condition $\alpha\le1$ such that the function $x^\alpha[\ln x-\psi(x)]$ is completely monotonic on $(0,\infty)$.

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Feng Qi, Bai-Ni Guo. 2009-02-15. Two new proofs of the complete monotonicity of a function involving the psi function. https://doi.org/10.4134/bkms.2010.47.1.103

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