Some new properties of the beta function and Ramanujan R-function

被引:0
作者
Yang, Zhen-Hang [1 ]
Wang, Miao-Kun [2 ]
Zhao, Tie-Hong [3 ]
机构
[1] State Grid Zhejiang Elect Power Co Res Inst, Dept Sci & Technol, Hangzhou 310014, Zhejiang, Peoples R China
[2] Huzhou Univ, Dept Math, Huzhou 313000, Zhejiang, Peoples R China
[3] Hangzhou Normal Univ, Sch Math, Hangzhou 311121, Zhejiang, Peoples R China
关键词
Beta function; Ramanujan function; Power series; Hypergeometric series; Complete monotonicity; Monotonicity; GENERALIZED ELLIPTIC INTEGRALS; ASYMPTOTIC EXPANSIONS; INEQUALITIES; MONOTONICITY; BOUNDS;
D O I
10.1007/s11139-025-01062-1
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
In this paper, the power series and hypergeometric series representations of the beta function and the Ramanujan R-function with one parameter, Bx=Gamma x2 Gamma 2xandRx=-2 psi x-2 gamma,\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\begin{aligned} {\mathcal {B}}\left( x\right) =\frac{\Gamma \left( x\right) <^>{2}}{\Gamma \left( 2x\right) }\text { and }{\mathcal {R}}\left( x\right) =-2\psi \left( x\right) -2\gamma , \end{aligned}$$\end{document}are presented, which yield higher order monotonicity results related to B(x)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\mathcal {B}}(x)$$\end{document} and R(x)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathcal {R}}(x)$$\end{document}; the decreasing property of the functions Rx/Bx\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathcal {R}}\left( x\right) /{\mathcal {B}}\left( x\right) $$\end{document} and [B(x)-R(x)]/x2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$[ {\mathcal {B}}(x) -{\mathcal {R}}(x)] /x<^>{2}$$\end{document} on 0,infinity\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\left( 0,\infty \right) $$\end{document} is proved. Moreover, a conjecture put forward by Qiu et al. in [17] is proved to be true. As applications, several inequalities and identities are deduced. These results obtained in this paper may be helpful for the study of certain special functions. Finally, an interesting infinite series similar to the Riemann zeta functions is mentioned and a relevant problem is proposed.
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页数:25
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