ACTA MATHEMATICA
UNIVERSITATIS COMENIANAE




Vol. LXXVII, 2 (2008)
p. 305 - 312

On the Hilbert Inequality

Zhou Yu and Gao Mingzhe

Received: August 3, 2007;   Accepted: February 21, 2008



Abstract.   In this paper it is shown that the Hilbert inequality for double series~can be improved by introducing a weight function of the form (Ö n)/(n + 1) (((Ö n) – 1)/((Ö n)+1) – (ln n)/π) ), where n Î N. A similar result for the Hilbert integral inequality is also given. As applications, some sharp results of Hardy-Littlewood's theorem and Widder's theorem are obtained.

Keywords:  Hilbert's inequality; weight function; double series; monotonic function; Hardy-Littlewood's theorem; Widder's theorem.  

AMS Subject classification: Primary:  26D15.


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Acta Mathematica Universitatis Comenianae
ISSN 0862-9544   (Printed edition)

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