A Class of Logarithmically Completely Monotonic Functions Associated with a Gamma Function [PDF]
Journal of Inequalities and Applications, 2010 We show that the function is strictly logarithmically completely monotonic on if and only if and is strictly logarithmically completely monotonic on if and only if .
Tie-Hong Zhao, Yu-Ming Chu
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Logarithmically Complete Monotonicity Properties Relating to the Gamma Function [PDF]
Abstract and Applied Analysis, 2011 We prove that the function fα,β(x)=Γβ(x+α)/xαΓ(βx) is strictly logarithmically completely monotonic on (0,∞) if (α,β)∈{( α,β):1/α≤β≤1, α≠1}∪{(α,β ...
Tie-Hong Zhao, Yu-Ming Chu, Hua Wang
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Necessary and sufficient conditions for a class of functions and their reciprocals to be logarithmically completely monotonic [PDF]
Journal of Inequalities and Applications, 2011 We prove that the function F α,β (x) = x α Γ β (x)/Γ(βx) is strictly logarithmically completely monotonic on (0, ∞) if and only if (α, β) ∈ {(α, β) : β > 0, β ≥ 2 ...
Lv Yu-Pei, Sun Tian-Chuan, Chu Yu-Ming
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A SOLUTION TO QI’S EIGHTH OPEN PROBLEM ON COMPLETE MONOTONICITY
Проблемы анализа, 2021 n this paper, the complete monotonicity of 1/( arctan 𝑥) is proved. This problem was posted by F. Qi and R. P. Agarwal as the eighth open problem of collection of eight open problems.
A. Venkata Lakshmi
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Sharp inequalities related to the volume of the unit ball in R n $\mathbb{R}^{n}$
Journal of Inequalities and Applications, 2023 Let Ω n = π n / 2 / Γ ( n 2 + 1 ) $\Omega _{n}=\pi ^{n/2}/\Gamma (\frac{n}{2}+1)$ ( n ∈ N $n \in \mathbb{N}$ ) denote the volume of the unit ball in R n $\mathbb{R}^{n}$ .
Xue-Feng Han, Chao-Ping Chen
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A complete monotonicity property of the multiple gamma function
Comptes Rendus. Mathématique, 2020 We consider the following functions \[ f_n(x)=1-\ln x+\frac{\ln G_n(x+1)}{x} \text{ and }g_n(x)=\frac{\@root x \of {G_n(x+1)}}{x},\; x\in (0,\infty ),\; n\in \mathbb{N}, \] where $G_n(z)=\left(\Gamma _n(z)\right)^{(-1)^{n-1}}$ and $\Gamma _n$ is the ...
Das, Sourav
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Complete monotonicity involving some ratios of gamma functions
Journal of Inequalities and Applications, 2017 In this paper, by using the properties of an auxiliary function, we mainly present the necessary and sufficient conditions for various ratios constructed by gamma functions to be respectively completely and logarithmically completely monotonic.
Zhen-Hang Yang, Shen-Zhou Zheng
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On complete monotonicity for several classes of functions related to ratios of gamma functions
Journal of Inequalities and Applications, 2019 Let Γ(x) $\varGamma (x)$ denote the classical Euler gamma function. The logarithmic derivative ψ(x)=[lnΓ(x)]′=Γ′(x)Γ(x) $\psi (x)=[\ln \varGamma (x)]'=\frac{\varGamma '(x)}{ \varGamma (x)}$, ψ′(x) $\psi '(x)$, and ψ″(x) $\psi ''(x)$ are, respectively ...
Feng Qi, Ravi P. Agarwal
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A completely monotonic function involving the gamma and trigamma functions
Kuwait Journal of Science, 2016 In the paper the author provides necessary and sufficient conditions on $a$ for the function\begin{equation*}\frac{1}{2}\ln(2\pi)-x+\biggl(x-\frac{1}{2}\biggr)\ln x-\ln\Gamma(x)+\frac1{12}{\psi'(x+a)}\end{equation*}and its negative to be completely ...
Feng Qi
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REMARKS ON COMPLETE MONOTONICITY OF A FUNCTION INVOLVING THE GAMMA FUNCTION
Проблемы анализа, 2015 In the note, the authors give several remarks on the paper in "Chen and Haigang Zhou On completely monotone of an arbitrary real parameter function involving the gamma function. Applied Mathematics and Compulation, 2014, vol. 242, pp.
F. Qi, B. N. Guo
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