Efficient approximations of the gamma function and further properties

被引：2

作者：

Mortici, Cristinel ^{[1
,2
]}

Dumitrescu, Sorinel ^{[3
]}

机构：

[1] Valahia Univ Targoviste, Bd Unirii 18, Targoviste 130082, Romania

[2] Acad Romanian Scientists, Splaiul Independentei 54, Bucharest 50094, Romania

[3] Univ Politehn Bucuresti, Splaiul Independentei 313, Bucharest, Romania

来源：

COMPUTATIONAL & APPLIED MATHEMATICS | 2017年 / 36卷 / 01期

关键词：

Gamma function; Digamma function; Approximations; Error estimates; Speed of convergence; Asymptotic series; Complete monotonicity; Inequalities; FACTORIAL FUNCTION; FORMULA; CONSTANT;

D O I：

10.1007/s40314-015-0252-1

中图分类号：

O29 [应用数学];

学科分类号：

070104 ;

摘要：

The aim of this paper is to introduce some simple and fast formulas for approximating the gamma function. Some involved functions are completely monotonic. The corresponding asymptotic series are constructed and some sharp inequalities are established.

引用

页码：677 / 691

页数：15

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