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Related papers: On Some Properties of the Trigamma Function

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In this paper, the authors establish some inequalities involving the Psi and $k$-Gamma functions. The procedure utilizes some monotonicity properties of some functions associated with the Psi and $k$-Gamma functions.

Classical Analysis and ODEs · Mathematics 2016-02-17 Kwara Nantomah

Neither the Euler-Mascheroni constant, $\gamma=0.577215\ldots$, nor the Euler-Gompertz constant, $\delta=0.596347\ldots$, is currently known to be irrational. However, it has been proved that these two numbers are disjunctively…

Number Theory · Mathematics 2025-08-26 Michael R. Powers

We consider a uniformly rectifiable set $\Gamma \subset \mathbb R^n$ of dimension $d<n-1$. By using degenerate elliptic operators on the complement $\Omega = \mathbb R^n \setminus \Gamma$, Guy David, Svitlana Mayboroda, and the author…

Analysis of PDEs · Mathematics 2022-07-26 Joseph Feneuil

In this note, we prove that for all $x \in (0 , 1)$, we have: $$ \log\Gamma(x) = \frac{1}{2} \log\pi + \pi \boldsymbol{\eta} \left(\frac{1}{2} - x\right) - \frac{1}{2} \log\sin(\pi x) + \frac{1}{\pi} \sum_{n = 1}^{\infty} \frac{\log n}{n}…

Number Theory · Mathematics 2013-12-30 Bakir Farhi

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

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

We consider the sum $\sum 1/\gamma$, where $\gamma$ ranges over the ordinates of nontrivial zeros of the Riemann zeta-function in an interval $(0,T]$, and consider the behaviour of the sum as $T \to\infty$. We show that, after subtracting a…

Number Theory · Mathematics 2021-07-02 Richard P. Brent , David J. Platt , Timothy S. Trudgian

We study the properties of a function $\psi(z, q)$ (the generalized polygamma function), intimately connected with the Hurwitz zeta function and defined for complex values of the variables $z$ and $q$, which is entire in the variable $z$…

Classical Analysis and ODEs · Mathematics 2008-11-07 Olivier Espinosa , Victor H. Moll

This paper has two parts. The first part surveys Euler's work on the constant gamma=0.57721... bearing his name, together with some of his related work on the gamma function, values of the zeta function and divergent series. The second part…

Number Theory · Mathematics 2013-10-28 Jeffrey C. Lagarias

From a well-known equation of Hardy, one can derive a simple linear combination of the Euler-Mascheroni constant ($\gamma=0.577215\ldots$) and Euler-Gompertz constant ($\delta=0.596347\ldots$): $\gamma+\delta/e=\textrm{Ein}\left(1\right)$.…

Number Theory · Mathematics 2025-10-02 Michael R. Powers

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

The research shows that Riemann proved that all of zeros of Riemann's zeta function are on $\sigma=1/2$ based on the functional equation \begin{align*} \pi^{-\frac{s}{2}}\Gamma \left( \frac{s}{2} \right) \zeta(s)&={\frac{1}{s(s-1)} +…

General Mathematics · Mathematics 2022-11-07 Nianrong Feng , Yongzheng Wang

We define an absolutely convergent series for the upper incomplete Gamma function $\Gamma(s,z)$ for $z\geq 1$ and $s\in \mathbb{C}$. We express this series using certain polynomials which we define using the Stirling numbers of the first…

Combinatorics · Mathematics 2019-09-17 Mario DeFranco

Let $\alpha>0$ be a constant, let $\ell\ge0$ be an integer, and let $\Gamma(z)$ denote the classical Euler gamma function. With the help of the integral representation for the Riemann zeta function $\zeta(z)$, by virtue of a monotonicity…

Number Theory · Mathematics 2022-01-19 Bai-Ni Guo , Feng Qi

We study absolute continuity of harmonic measure with respect to surface measure on domains $\Omega$ that have large complements. We show that if $\Gamma\subset \mathbb{R}^{d+1}$ is $d$-Ahlfors regular and splits $ \mathbb{R}^{d+1}$ into…

Classical Analysis and ODEs · Mathematics 2016-08-29 Murat Akman , Jonas Azzam , Mihalis Mourgoglou

Let $u$ and $v$ be harmonic in $ \Omega \subset \mathbb{R}^n$ functions with the same zero set $Z$. We show that the ratio $f$ of such functions is always well-defined and is real analytic. Moreover it satisfies the maximum and minimum…

Analysis of PDEs · Mathematics 2015-03-10 Alexander Logunov , Eugenia Malinnikova

A class of functions involving the divided differences of the psi function and the polygamma functions and originating from Kershaw's double inequality are proved to be completely monotonic. As applications of these results, the…

Classical Analysis and ODEs · Mathematics 2011-05-13 Feng Qi , Bai-Ni Guo

In 1981, Sacks and Uhlenbeck introduced their famous $\alpha$-energy as a way to approximate the Dirichlet energy and produce harmonic maps from surfaces into Riemannian manifolds. However, the second and third authors together with…

Differential Geometry · Mathematics 2022-06-01 Jasmin Hörter , Tobias Lamm , Mario Micallef

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

We introduce a gamma function $\Ga(x,z)$ in two complex variables which extends the classical gamma function $\Ga(z)$ in the sense that $\lim_{x\to 1}\Ga(x,z)=\Ga(z)$. We will show that many properties which $\Ga(z)$ enjoys extend in a…

Number Theory · Mathematics 2026-04-10 Mohamed El Bachraoui