Bounds for the Ratio of Two Gamma Functions
نویسنده
چکیده
Feng Qi Department of Mathematics, College of Science, Tianjin Polytechnic University, Tianjin City 300160, China Correspondence should be addressed to Feng Qi, [email protected], [email protected] Received 28 July 2009; Accepted 16 January 2010 Academic Editor: László Losonczi Copyright q 2010 Feng Qi. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. By looking back at the long history of bounding the ratio Γ x a /Γ x b for x > −min{a, b} and a, b ∈ R, various origins of this topic are clarified, several developed courses are followed, different results are compared, useful methods are summarized, new advances are presented, some related problems are pointed out, and related references are collected.
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Bounds for the Ratio of Two Gamma Functions—from Gautschi’s and Kershaw’s Inequalities to Completely Monotonic Functions
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