Abstract
The main object of this paper is to propose a product approximation for the gamma function. The estimates derived here are studied via the theory of completely monotonic functions. Sharp inequalities are stated.
Similar content being viewed by others
References
Abramowitz, M., Stegun, I. A. (eds.): Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables. Applied Mathematics Series 55, National Bureau of Standards, Washington, D.C. 1964. Reprinted by Dover Publications, New York (1972)
Alzer, H.: On some inequalities for the gamma and psi functions. Math. Comput. 66, 373–389 (1997)
Erdélyi, A., Magnus, W., Oberhettinger, F., Tricomi, F. G: Higher Transcendental Functions, Vols. I, McGraw-Hill Book Company, New York, Toronto and London, 1953,1953 and (1955)
Mortici, C.: Product approximation via asymptotic integration. Amer. Math. Monthly 117, 434–441 (2010)
Mortici, C.: A quicker convergence toward the gamma constant with the logarithm term involving the constant e. Carpathian J. Math. 26, 86–91 (2010)
Mortici, C.: A new Stirling series as continued fraction. Numer. Algorithms 56(1), 17–26 (2011)
Ramanujan, S.: The Lost Notebook and Other Unpublished Papers Narosa Publishing Company (Springer), New Delhi and Berlin, 1988
Sándor, J., Debnath, L.: On certain inequalities involving the constant e and their applications. J. Math. Anal. Appl. 249, 569–582 (2000)
Whittaker, E.T., Watson, G.N.: A course of modern analysis: an introduction to the general theory of infinite processes and of analytic functions; with an account of the principal transcendental Functions, Fourth Edition. Cambridge University Press, Cambridge, London and New York (1927)
Widder, D.V: The laplace transform. Princeton University Press, Princeton (1941)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Mortici, C., Srivastava, H.M. A product approximation of the gamma function. Numer Algor 69, 595–610 (2015). https://doi.org/10.1007/s11075-014-9915-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11075-014-9915-z
Keywords
- Factorial function
- Gamma function
- Product approximations
- Stirling’s formula
- Asymptotic series
- Two-sided inequalities
- Complete monotonicity
- Speed of convergence
- Haussdorff-Bernstein-Widder theorem
- Numerical computations