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Related papers: Inequalities for the Psi and $k$-Gamma Functions

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In this paper, two sharp inequalities for bounding the psi function $\psi$ and the harmonic numbers $H_n$ are established respectively, some results in [I. Muqattash and M. Yahdi, \textit{Infinite family of approximations of the Digamma…

Classical Analysis and ODEs · Mathematics 2014-06-04 Feng Qi , Bai-Ni Guo

In the paper, we present a monotonicity result of a function involving the gamma function and the logarithmic function, refine a double inequality for the gamma function, and improve some known results for bounding the gamma function.

Classical Analysis and ODEs · Mathematics 2012-05-21 Feng Qi , Bai-Ni Guo

In this paper, we present the (p; q)-analogues of some inequalities concerning the digamma function. Our results generalize some earlier results.

Classical Analysis and ODEs · Mathematics 2014-08-15 Kwara Nantomah

Simple inequalities for some integrals involving the modified Bessel functions $I_{\nu}(x)$ and $K_{\nu}(x)$ are established. We also obtain a monotonicity result for $K_{\nu}(x)$ and a new lower bound, that involves gamma functions, for…

Classical Analysis and ODEs · Mathematics 2017-03-21 Robert E. Gaunt

We prove that certain functions involving ratios of Gamma functions and the Psi-function belong to generalized Bernstein classes and new properties of generalized Bernstein functions are given.

Classical Analysis and ODEs · Mathematics 2025-07-08 Stamatis Koumandos , Henrik L. Pedersen

We introduce new generalizations of the Gamma and the Beta functions. Their properties are investigated and known results are obtained as particular cases.

Number Theory · Mathematics 2015-06-25 P. Njionou Sadjang

In this expository and survey paper, along one of main lines of bounding the ratio of two gamma functions, we look back and analyse some inequalities, the complete monotonicity of several functions involving ratios of two gamma or $q$-gamma…

Classical Analysis and ODEs · Mathematics 2014-11-04 Feng Qi

Motivated by several conjectures posed in the paper " Completely monotonic degrees for a difference between the logarithmic and psi functions",we confirm in this work some conjectures on completely monotonic degrees of remainders of the…

Classical Analysis and ODEs · Mathematics 2022-02-07 Mohamed Bouali

We prove some new results and unify the proofs of old ones involving complete monotonicity of expressions involving gamma and $q$-gamma functions, $0 < q < 1$. Each of these results implies the infinite divisibility of a related probability…

Classical Analysis and ODEs · Mathematics 2013-01-10 Mourad E. H. Ismail , Martin E. Muldoon

Some inequalities for the ratios of generalized digamma functions are presented. The approache makes use of the series representations of the $(q,k)$-digamma and $(p,q)$-digamma functions.

Classical Analysis and ODEs · Mathematics 2014-08-18 Kwara Nantomah

This paper is inspired by the work of J. S\'{a}ndor in 2006. In the paper, the authors establish some double inequalities involving the ratio $ \frac{\Gamma_{q}(x+1)}{ \Gamma_{q} \left( x+\frac{1}{2}\right)}$, where $\Gamma_{q}(x)$ is the…

Classical Analysis and ODEs · Mathematics 2015-07-01 Kwara Nantomah , Edward Prempeh

In this paper, we present some new inequalities for the gamma function. The main tools are the multiple-correction method developed in our previous works, and a generalized Mortici's lemma.

Classical Analysis and ODEs · Mathematics 2015-03-18 Xiaodong Cao

In this paper, we introduce a new two-parameter deformation of the Gamma function that generalizes some existing Gamma-type functions in the literature. We study properties of this function that depend on the parameters. We also prove some…

Classical Analysis and ODEs · Mathematics 2025-10-10 Anton Asare-Tuah , Emmanuel Djabang , Eyram A. K. Schwinger , Benoit F. Sehba , Ralph A. Twum

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

An inequality concerning ratios of gamma functions is proved. This answers a question of Guo and Qi (2003).

Classical Analysis and ODEs · Mathematics 2009-09-22 Yaming Yu

In this article, a necessary and sufficient condition and a necessary condition are established for a function involving the gamma function to be logarithmically completely monotonic on $(0,\infty)$. As applications of the necessary and…

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

Recently, extensions of gamma and beta functions have been studied by many researchers due to their nice properties and variety of applications in different fields of science. The aim of this note is to investigate generalized inequalities…

General Mathematics · Mathematics 2024-07-18 S. Mubeen , I. Aslam , Ghazi S. Khammash , Saralees Nadarajah , Ayman Shehata

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 polygamma functions, where $\Gamma(x)$ is the gamma function. In this paper, we prove that the function $$…

Classical Analysis and ODEs · Mathematics 2015-05-12 Feng Qi

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

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