Sharp inequalities for factorial n


  • Necdet Batir Yunzuncu Yil University.



Factorial n, gamma function, Stirling’s formula, Burnside’s formula, función gamma, fórmula de Stirling, fórmula de Burnside.


Let n be a positive integer. We prove

with the best possible constants

This refines and extends a result of Sandor and Debnath, who proved that the double inequality holds with a = 0 and ß = 1.

Author Biography

Necdet Batir, Yunzuncu Yil University.

Faculty of Arts and Sciences.
Department of Mathematics.


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How to Cite

N. Batir, “Sharp inequalities for factorial n”, Proyecciones (Antofagasta, On line), vol. 27, no. 1, pp. 97-102, May 2017.