Ramanujan’s approximation to the exponential function and generalizations

被引：0
作者：
Cormac O’Sullivan
机构：
[1] The CUNY Graduate Center,Department of Mathematics
来源：
The Ramanujan Journal | 2023年 / 62卷
关键词：
Exponential function; Gamma function; Saddle-point method; Exponential integral; 33B10; 30E15;
D O I：
暂无
中图分类号：
学科分类号：
摘要：
Ramanujan’s approximation to the exponential function is reexamined with the help of Perron’s saddle-point method. This allows for a wide generalization that includes the results of Buckholtz, and where all the asymptotic expansion coefficients may be given in closed form. Ramanujan’s approximation to the exponential integral is treated similarly.
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页码：649 / 673
页数：24
相关论文
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