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A new lower bound in the second Kershaw’s double inequality. (English) Zbl 1142.26020
Summary: A new and elegant lower bound in the second Kershaw’s double inequality is established, some alternative simple and polished proofs are given, several deduced functions involving the gamma and psi functions are proved to be decreasingly monotonic and logarithmically completely monotonic, and some remarks and comparisons are stated.

MSC:
26D20Analytical inequalities involving real functions
33B10Exponential and trigonometric functions
33B15Gamma, beta and polygamma functions
References:
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