A class of completely mixed monotonic functions involving the gamma function with applications

Yang, Zhen-Hang; Tian, Jing-Feng

doi:10.1090/proc/14199

A class of completely mixed monotonic functions involving the gamma function with applications

Authors: Zhen-Hang Yang and Jing-Feng Tian
Journal: Proc. Amer. Math. Soc. 146 (2018), 4707-4721
MSC (2010): Primary 33B15, 26B25; Secondary 26D15
DOI: https://doi.org/10.1090/proc/14199
Published electronically: August 10, 2018
MathSciNet review: 3856139
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Abstract: In this paper, we introduce the notion of completely mixed monotonicity of a function of several variables, very few of which have appeared. We give a necessary and sufficient condition for a function constructed by ratios of gamma functions to be completely mixed monotonic. From this, some new inequalities for gamma, psi, and polygamma functions are derived.

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