Proceedings of the American Mathematical Society

Author(s): Stamatis Koumandos
Journal: Proc. Amer. Math. Soc. 134 (2006), 1365-1367.
MSC (2000): Primary 33B15; Secondary 26D20
Posted: October 6, 2005
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Abstract: In a recent paper, Chao-Ping Chen and Feng Qi (2005) established sharp upper and lower bounds for the sequence $P_{n}:=\frac{1.3\ldots (2n-1)}{2.4\ldots 2n}$ . We show that their result follows easily from a theorem of G. N Watson published in 1959. We also show that the main result of Chen and Qi's paper is a special case of a more general inequality which admits a very short proof.

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