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arXiv 1408.3902math.NTmath.CO
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与$π^{-1}$有关的仅含有理系数的含Stirling数的Γ函数对数的两个级数展开式

Two series expansions for the logarithm of the gamma function involving Stirling numbers and containing only rational coefficients for certain arguments related to $π^{-1}$

Iaroslav V. Blagouchine

摘要:

本文给出并研究了$Γ$ -函数的两个新的对数级数.它们的polygamma类似物也获得和讨论。这些级数涉及第一类斯特林数,并且具有仅包含与$π^{-1}$相关的某些参数的有理系数的性质。特别地,对于形式为$\lnΓ(\frac{1}{2}n\pmαπ^{-1})$和$Ψ_k(\frac{1}{2}n\pmαπ^{-1})$的任何值,其中$Ψ_k$代表$k$ th polygamma函数,$α$是大于$\frac{1}{6}π$的正有理数,$n$是整数并且$k$是非负整数,这些级数仅具有有理数项。在指定的收敛区域中,派生级数以与$\sum(n\ln^m\!n)^{-2}$相同的速率一致收敛,其中$m=1, 2, 3,\ldots$ \,取决于polygamma函数的阶数。对于最吸引的值,如$\lnΓ(π^{-1})$,$\lnΓ(2π^{-1})$,$\lnΓ(\tfrac{1}{2}+π^{-1})$,$Ψ(π^{-1})$,$Ψ(\tfrac{1}{2}+π^{-1})$和$Ψ_k(π^{-1})$,给出了有理系数级数的显式展开式.此外,在本文中,读者还将发现一些其他系列涉及斯特林数,格雷戈里系数(对数数,也称为第二类伯努利数),柯西数和广义伯努利数。最后,得到了Gregory系数、Cauchy数、某些广义Bernoulli数以及某些Stirling数和的估计和完全渐近性.特别是,这些包括尖锐的边界格雷戈里的系数和柯西数的第二种。

英文摘要:

In this paper, two new series for the logarithm of the $Γ$-function are presented and studied. Their polygamma analogs are also obtained and discussed. These series involve the Stirling numbers of the first kind and have the property to contain only rational coefficients for certain arguments related to $π^{-1}$. In particular, for any value of the form $\lnΓ(\frac{1}{2}n\pmαπ^{-1})$ and $Ψ_k(\frac{1}{2}n\pmαπ^{-1})$, where $Ψ_k$ stands for the $k$th polygamma function, $α$ is positive rational greater than $\frac{1}{6}π$, $n$ is integer and $k$ is non-negative integer, these series have rational terms only. In the specified zones of convergence, derived series converge uniformly at the same rate as $\sum(n\ln^m\!n)^{-2}$, where $m=1, 2, 3,\ldots$\,, depending on the order of the polygamma function. Explicit expansions into the series with rational coefficients are given for the most attracting values, such as $\lnΓ(π^{-1})$, $\lnΓ(2π^{-1})$, $\lnΓ(\tfrac{1}{2}+π^{-1})$, $Ψ(π^{-1})$, $Ψ(\tfrac{1}{2}+π^{-1})$ and $Ψ_k(π^{-1})$. Besides, in this article, the reader will also find a number of other series involving Stirling numbers, Gregory's coefficients (logarithmic numbers, also known as Bernoulli numbers of the second kind), Cauchy numbers and generalized Bernoulli numbers. Finally, several estimations and full asymptotics for Gregory's coefficients, for Cauchy numbers, for certain generalized Bernoulli numbers and for certain sums with the Stirling numbers are obtained. In particular, these include sharp bounds for Gregory's coefficients and for the Cauchy numbers of the second kind.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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