Wendel's and Gautschi's inequalities: Refinements, extensions, and a class of logarithmically completely monotonic functions

نویسندگان

  • Feng Qi
  • Bai-Ni Guo
چکیده

In the article, presented are sufficient and necessary conditions for a class of functions involving the ratio of two gamma functions to be logarithmically completely monotonic. From this, some inequalities for bounding the ratio of two gamma functions are refined, extended and sharpened readily, and double inequalities on the divided differences of the psi and polygamma functions are derived straightforwardly.

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عنوان ژورنال:
  • Applied Mathematics and Computation

دوره 205  شماره 

صفحات  -

تاریخ انتشار 2008