Necessary and sufficient conditions for functions involving the tri- and tetra-gamma functions to be completely monotonic

Advances in Applied Mathematics

Volumn 44, Issue 1, 2010, Pages 71-83

  Qi, Feng ^a,b   Guo, Bai Ni ^b  

^a HENAN NORMAL UNIVERSITY   (China)

^b HENAN POLYTECHNIC UNIVERSITY   (China)

Author keywords

Complete monotonicity; Convexity; Monotonicity; Psi function; Tetra gamma function; Tri gamma function

Indexed keywords

COMPLETE MONOTONICITY; CONVEXITY; MONOTONICITY; PSI FUNCTION; TETRA-GAMMA FUNCTION; TRI-GAMMA FUNCTION;

MATHEMATICAL TECHNIQUES;

TRAJECTORIES;

EID: 70349974081     PISSN: 01968858     EISSN: 10902074     Source Type: Journal    
DOI: 10.1016/j.aam.2009.03.003     Document Type: Article

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