Paper Title:

Alternative Proofs for the Positivity of a Function Involving the Product of Two Digamma Functions

Author(s):

Ye Shuang, Dongkyu Lim* and Feng Qi

College of Mathematical Sciences,
Inner Mongolia Minzu University,
Tongliao 028043, Inner Mongolia,
China.
E-mail: shuangye152300@sina.com
URL: https://orcid.org/0000-0002-1991-4828

 Department of Mathematics Education,
Gyeongkuk National University,
Andong 36729,
Republic of Korea.
E-mail:  dklim@gknu.ac.kr
URL: https://orcid.org/0000-0002-0928-8480

School of Mathematics and Physics,
Hulunbuir University,
Hulunbuir 021008, Inner Mongolia,
China.
17709 Sabal Court, University Village,
Dallas, TX 75252-8025,
USA.
E-mail: qifeng618@gmail.com
URL: https://orcid.org/0000-0001-6239-2968
 

Abstract:

Let ψ(x) be the digamma function, that is, the logarithmic derivative of the classical Euler's gamma function Γ(x). In this paper, the authors alternatively prove the positivity of the function

Full Text PDF: