Results 21 to 30 of about 360,646 (291)
Some inequalities involving the polygamma functions
Journal of Inequalities and Applications, 2019 Let ψn(x)=(−1)n−1ψ(n)(x) $\psi _{n}(x)=(-1)^{n-1}\psi ^{(n)}(x)$, where ψ(n)(x) $\psi ^{(n)}(x)$ are the polygamma functions. We determine necessary and sufficient conditions for the monotonicity and convexity of the function F(x;α,β)=ln(exp(αψ(x+β))ψn(x)
Lichun Liang, Bin Zhao, Aibing Li
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Fractional inclusions of the Hermite–Hadamard type for m-polynomial convex interval-valued functions
Advances in Difference Equations, 2020 The notion of m-polynomial convex interval-valued function Ψ = [ ψ − , ψ + ] $\Psi =[\psi ^{-}, \psi ^{+}]$ is hereby proposed. We point out a relationship that exists between Ψ and its component real-valued functions ψ − $\psi ^{-}$ and ψ + $\psi ^{+}$ .
Eze R. Nwaeze +2 more
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A completely monotonic function involving the tri- and tetra-gamma functions
, 2010 The psi function $\psi(x)$ is defined by $\psi(x)=\frac{\Gamma'(x)}{\Gamma(x)}$ and $\psi^{(i)}(x)$ for $i\in\mathbb{N}$ denote the polygamma functions, where $\Gamma(x)$ is the gamma function.
Guo, Bai-Ni, Qi, Feng
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AxiomsWe systematically exploit a new generalized hypergeometric identity to obtain new hypergeometric summation formulas. As a consistency test, alternative proofs for some special cases are also provided.
Juan Luis González-Santander
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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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Some completely monotonic functions related to the psi function [PDF]
Mathematical Inequalities & Applications, 2011 Complete monotonicity properties of some functions involving the psi function are studied and some known results are extended and generalized. Moreover, a necessary and sufficient conditions for some functions to be completely monotonic are presented and proved.
Elezović, Neven, Burić, Tomislav
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On the Distribution of Plasmoids In High-Lundquist-Number Magnetic Reconnection
, 2012 The distribution function $f(\psi)$ of magnetic flux $\psi$ in plasmoids formed in high-Lundquist-number current sheets is studied by means of an analytic phenomenological model and direct numerical simulations.
Bhattacharjee, A., Huang, Yi-Min
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On rational bounds for the gamma function
Journal of Inequalities and Applications, 2017 In the article, we prove that the double inequality x 2 + p 0 x + p 0 < Γ ( x + 1 ) < x 2 + 9 / 5 x + 9 / 5 $$ \frac{x^{2}+p_{0}}{x+p_{0}}< \Gamma(x+1)< \frac{x^{2}+9/5}{x+9/5} $$ holds for all x ∈ ( 0 , 1 ) $x\in(0, 1)$ , we present the best possible ...
Zhen-Hang Yang +3 more
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Monotonicity of the incomplete gamma function with applications
Journal of Inequalities and Applications, 2016 In the article, we discuss the monotonicity properties of the function x → ( 1 − e − a x p ) 1 / p / ∫ 0 x e − t p d t $x\rightarrow (1-e^{-ax^{p}} )^{1/p}/\int_{0}^{x}e^{-t^{p}}\,dt$ for a , p > 0 $a, p>0$ with p ≠ 1 $p\neq1$ on ( 0 , ∞ ) $(0, \infty ...
Zhen-Hang Yang, Wen Zhang, Yu-Ming Chu
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The ${\bar c} c$ purity of $\psi(3770)$ and $\psi'$ challenged
, 2005 It is suggested that the resonance $\psi(3770)$ may contain a sizeable ($O(10%)$ in terms of the probability weight factor) four-quark component with the up- and down- quarks and antiquarks in addition to the $c {\bar c}$ pair, which component in itself ...
B. L. Ioffe +7 more
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