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Related papers: On functional inequalities for the psi function

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Motivated by several conjectures posed in the paper "F. Qi and A.-Q. Liu, Completely monotonic degrees for a difference between the logarithmic and psi functions, J. Comput. Appl. Math., vol. 361, pp. 366--371 (2019); available online at…

Classical Analysis and ODEs · Mathematics 2022-01-20 Feng Qi , Mansour Mahmoud

The logarithmic convexity of restrictions of the Beta functions to rays parallel to the main diagonal and the functional equation \[ \phi\left( x+1\right) =\frac{x\left( x+k\right) }{\left( 2x+k+1\right) \left( 2x+k\right) }\phi\left(…

Classical Analysis and ODEs · Mathematics 2015-05-07 Martin Himmel , Janu sz Matkowski

We prove that the function $g(x)= 1 / \bigl( 1 - \cos(x) \bigr)$ is completely monotonic on $(0,\pi]$ and absolutely monotonic on $[\pi, 2\pi)$, and we determine the best possible bounds $\lambda_n$ and $\mu_n$ such that the inequalities $$…

Classical Analysis and ODEs · Mathematics 2024-06-14 Horst Alzer , Henrik L. Pedersen

In the article we present necessary and sufficient conditions for a function involving the logarithm of the gamma function to be completely monotonic and apply these results to bound the gamma function $\Gamma(x)$, the $n$-th harmonic…

Classical Analysis and ODEs · Mathematics 2014-12-02 Feng Qi

We present some completely monotonic functions involving the $q$-gamma function that are inspired by their analogues involving the gamma function.

Classical Analysis and ODEs · Mathematics 2010-11-16 Peng Gao

In this paper, we consider the monotonicity of certain combinations of the Gaussian hypergeometric functions $F(a-1,b;a+b;1-x^c)$ and $F(a-1-\delta,b+\delta;a+b;1-x^d)$ on $(0,1)$ for $\delta\in(a-1,0)$, and study the problem of comparing…

Classical Analysis and ODEs · Mathematics 2016-09-29 Ti-Ren Huang , Xiao-Yan Ma , Xiao-Hui Zhang

In present paper, we prove the monotonicity of two functions involving the gamma function $\Gamma(x)$ and relating to the $n$-dimensional volume of the unit ball $\mathbb{B}^n$ in $\mathbb{R}^n$.

Classical Analysis and ODEs · Mathematics 2012-08-21 Feng Qi , Bai-Ni Guo

In this paper we investigate analytic inequalities related to a conjecture of Henry involving the difference between the Riemann zeta function and the digamma function. By treating $\zeta(s)-\psi(1-s)$ as a unified analytic object, we…

Number Theory · Mathematics 2026-01-15 Liwen Gao , Xuejun Guo

The main aim of this paper is to prove that the double inequality \frac{(k-1)!}{\Bigl\{x+\Bigl[\frac{(k-1)!}{|\psi^{(k)}(1)|}\Bigr]^{1/k}\Bigr\}^k}…

Classical Analysis and ODEs · Mathematics 2015-03-30 Feng Qi , Bai-Ni Guo

In this note, in particular, we establish the following result: Let $X$ be a real Banach space, $\varphi\in X^*\setminus \{0\}$ and $\psi:X\to {\bf R}$ a Lipschitzian functional with Lipschitz constant equal to $\varphi\|_X^{*}$. Then, we…

Functional Analysis · Mathematics 2016-02-24 Biagio Ricceri

We establish sharp inequalities involving the incomplete Beta and Gamma functions. These inequalities arise in the approximation of generalized Bernstein functions by higher order Thorin-Bernstein functions. Furthermore, new properties of a…

Classical Analysis and ODEs · Mathematics 2024-09-05 Stamatis Koumandos , Henrik Laurberg Pedersen

In the paper, the authors establish some asymptotic formulas and double inequalities for the factorial $n!$ and the gamma function $\Gamma$ in terms of the tri-gamma function $\psi'$.

Classical Analysis and ODEs · Mathematics 2015-06-02 Cristinel Mortici , Feng Qi

In the paper, by establishing the monotonicity of some functions involving the sine and cosine functions, the authors provide concise proofs of some known inequalities and find some new sharp inequalities involving the Seiffert,…

Classical Analysis and ODEs · Mathematics 2013-01-29 Wei-Dong Jiang , Feng Qi

We prove some properties of completely monotonic functions and apply them to obtain results on gamma and $q$-gamma functions.

Classical Analysis and ODEs · Mathematics 2011-11-10 Peng Gao

Bernoulli type inequalities for functions of logarithmic type are given. These functions include, in particular, Gaussian hypergeometric functions in the zero-balanced case $F(a,b;a+b;x)\,.$

Classical Analysis and ODEs · Mathematics 2016-05-30 Riku Klén , Vesna Manojlović , Slavko Simić , Matti Vuorinen

We prove a monotonicity property of the Hurwitz zeta function which, in turn, translates into a chain of inequalities for polygamma functions of different orders. We provide a probabilistic interpretation of our result by exploiting a…

Statistics Theory · Mathematics 2020-03-25 Julyan Arbel , Olivier Marchal , Bernardo Nipoti

We investigate conditions for logarithmic complete monotonicity of product ratios of gamma and q-gamma functions whose arguments are linear functions of the variable. We give necessary and sufficient conditions in terms of nonnegativity of…

Classical Analysis and ODEs · Mathematics 2020-04-30 Christian Berg , Asena Cetinkaya , Dmitrii Karp

We prove a matrix trace inequality for completely monotone functions and for Bernstein functions. As special cases we obtain non-trivial trace inequalities for the power function x->x^q, which for certain values of q complement McCarthy's…

Functional Analysis · Mathematics 2013-04-23 Koenraad M. R. Audenaert

We mainly establish a monotonicity property between some special Riemann sums of a convex function $f$ on $[a,b]$, which in particular yields that $\frac{b-a}{n+1}\sum_{i=0}^n f\left(a+i\frac{b-a}{n}\right)$ is decreasing while…

Classical Analysis and ODEs · Mathematics 2014-10-07 Jamal Rooin , Hossein Dehghan

The beta distribution is a two-parameter family of probability distributions whose distribution function is the (regularised) incomplete beta function. In this paper, the inverse incomplete beta function is studied analytically as…

Classical Analysis and ODEs · Mathematics 2017-10-27 Dimitris Askitis