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SOME LOGARITHMICALLY COMPLETELY MONOTONIC FUNCTIONS RELATED TO THE GAMMA FUNCTION

  • Qi, Feng (SCHOOL OF MATHEMATICS AND INFORMATICS HENAN POLYTECHNIC UNIVERSITY) ;
  • Guo, Bai-Ni (SCHOOL OF MATHEMATICS AND INFORMATICS HENAN POLYTECHNIC UNIVERSITY)
  • Received : 2009.03.30
  • Published : 2010.11.01

Abstract

In this article, the logarithmically complete monotonicity of some functions such as $\frac{1}{[\Gamma(x+1)]^{1/x}$, $\frac{[\Gamma(x+1)]^{1/x}}{x^\alpha}$, $\frac{[\Gamma(x+1)]^{1/x}}{(x+1)^\alpha}$ and $\frac{[\Gamma(x+\alpha+1)]^{1/(x+\alpha})}{[\Gamma(x+1)^{1/x}}$ for $\alpha{\in}\mathbb{R}$ on ($-1,\infty$) or ($0,\infty$) are obtained, some known results are recovered, extended and generalized. Moreover, some basic properties of the logarithmically completely monotonic functions are established.

Keywords

References

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