The Laplace transform of the psi function
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Abstract:
An expression for the Laplace transform of the psi function \begin{equation} L(a):=\int _{0}^{\infty }e^{-at}\psi (t+1) dt\nonumber \\ \end{equation} is derived using two different methods. It is then applied to evaluate the definite integral \begin{equation} M(a)=\frac {4}{\pi } \int _{0}^{\infty }\frac {x^2 dx}{x^2+\ln ^{2}(2e^{-a}\cos x)},\nonumber \\ \end{equation} for $a>\ln 2$ and to resolve a conjecture posed by Olivier Oloa.References
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Additional Information
- Atul Dixit
- Affiliation: Department of Mathematics, University of Illinois, 1409 West Green Street, Urbana, Illinois 61801
- MR Author ID: 734852
- Email: aadixit2@illinois.edu
- Received by editor(s): October 28, 2008
- Published electronically: September 25, 2009
- Communicated by: Peter A. Clarkson
- © Copyright 2009
American Mathematical Society
The copyright for this article reverts to public domain 28 years after publication. - Journal: Proc. Amer. Math. Soc. 138 (2010), 593-603
- MSC (2000): Primary 33B15
- DOI: https://doi.org/10.1090/S0002-9939-09-10157-0
- MathSciNet review: 2557176