与Gamma函数有关的对数完全单调函数及其应用 |
| |
引用本文: | 孙梅. 与Gamma函数有关的对数完全单调函数及其应用[J]. 纯粹数学与应用数学, 2016, 32(2): 212-220. DOI: 10.3969/j.issn.1008-5513.2016.02.013 |
| |
作者姓名: | 孙梅 |
| |
作者单位: | 西北大学数学学院,陕西 西安,710127 |
| |
基金项目: | 陕西省自然科学基金(2010JM1017) |
| |
摘 要: | 为了完善函数G_(α,β)(x)(其中参数α∈R,β≥0)及函数1/G_(α,β)(x)在区间(0,∞)上的对数完全单调性和相关不等式,利用Taylor展开式、Gamma函数、Psi函数的级数表达式和积分表达式研究了函数G_(α,β)(x)和函数1/G_(α,β)(x)数的对数完全单调性,将函数G_(α,β)(x)和函数1/G_(α,β)(x)对数完全单调的充分条件扩大;利用对数完全单调性得到新的不等式,并通过对特殊情形的研究,得到一个形式简单对称的双边不等式,该不等式对阶乘数之乘积与∏nk=1k~k的商做出估计.
|
关 键 词: | Gamma函数 对数完全单调函数 充分条件 不等式 |
The logarithmically completely momotonic functions related to the Gamma function with application |
| |
Abstract: | In order to improve the logarithmically completely monotonicity and related inequalities of the function Gα,β(x)(where α∈R, β ≥0 are parameter) and 1/Gα,β(x) which are defined in (0,∞). Using Taylor series expansion, the series expansion and integral expression of Gamma function and Psi function, this paper researches the logarithmically completely monotonicity of function Gα,β(x) and 1/Gα,β(x) and expands the su?cient condition. By the logarithmically completely monotonicities, a new inequality is established. Based on the research of the special circumstances, a symmetrical and concise two-side inequality, which estimates the division of factorial and∏nk=1 kk, is established. |
| |
Keywords: | Gamma function logarithmically completely momotonic function su?cient condition inequality |
本文献已被 CNKI 万方数据 等数据库收录! |
|