Yuan, Zhifang; Wang, Liantang Complete monotonicity of some specific functions. (Chinese. English summary) Zbl 1340.33003 Pure Appl. Math. 31, No. 2, 129-135 (2015). Summary: The classical Euler gamma function is one of the most important special functions and has many extensive applications in many branches, for examples, statistics, physics, engineering and so on. The complete monotonicity plays a central role in studying the special functions. In this paper, some complete monotonicity and logarithmically complete monotonicity of some functions involving gamma functions are proved and some sufficient and necessary conditions for some special functions to be completely monotonic or logarithmically completely monotonic are proposed. MSC: 33B15 Gamma, beta and polygamma functions 26A48 Monotonic functions, generalizations Keywords:complete monotonicity; logarithmically completely monotonicity; gamma function; psi function; sufficient and necessary conditions PDFBibTeX XMLCite \textit{Z. Yuan} and \textit{L. Wang}, Pure Appl. Math. 31, No. 2, 129--135 (2015; Zbl 1340.33003) Full Text: DOI