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arXiv · 1303.1582

Complete monotonicity of a difference between the exponential and trigamma functions

Feng Qi·Xiao-Jing Zhang
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Abstract

In the paper, by directly verifying an inequality which gives a lower bound for the first order modified Bessel function of the first kind, the authors supply a new proof for the complete monotonicity of a difference between the exponential function $e^{1/t}$ and the trigamma function $ψ'(t)$ on $(0,\infty)$.

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Feng Qi, Xiao-Jing Zhang. 2013-03-07. Complete monotonicity of a difference between the exponential and trigamma functions. https://doi.org/10.7468/jksmeb.2014.21.2.141

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