关于Smarandache函数与Riemann zeta-函数

对任意正整数n,著名的Smarandache函数S(n)定义为最小的正整数m使得n|m!.即S(n)=min{m∶m ∈N,n|m!).本文的主要目的是利用初等方法研究一类包含S(n)的Dirichlet级数与Riemann zeta-函数之间的关系,并得到了一个有趣的恒等式.     

一个包含Smarandache函数的方程

对于任意正整数n,我们用S(n)表示Smarandache函数,即S(n)=min{m:n|m!}.本文的主要目的是运用初等方法研究方程∑_(d|n)S(d)=n的可解性,并给出它的所有正整数解.     

一个包含Smarandache函数的复合函数

对任意正整数n,著名的Smarandache函数S(n)定义为最小的正整数m使得n|m!,或者S(n)=min{m∶n|m!,m∈N}.而函数Z(n)定义为最小的正整数k使得n≤k(k 1)/2,即就是Z(n)=min{k:n≤k(k 1)/2}.本文的主要目的是利用初等及解析方法研究复合函数S(Z(n))的均值,并给出一个较强的渐近公式.     

关于Smarandache函数S(n)与除数函数d(n)的混合均值

对于任意的正整数n,著名的Smarandache函数S(n)定义为最小的正整数m,使得n|m!,即就是S(n)=min{m:n|m!,m ∈N).本文的主要目的是应用初等方法研究S(n)与除数函数d(n)的加权均值问题,并获得一个有趣的渐进公式.     

关于Smarandache对偶函数

定义Smarandache对偶函数S*(n)为最大的正整数m使得m!|n.定义另一种双阶乘函数S**(n)为最大的正整数2m-1使得(2m-1)!!|n,其中2 n;且当2|n时,为最大的正整数2m使得(2m)!!|n.本文的主要目的是利用初等方法研究一个包含S**(n)的无穷级数的收敛性,并给出一个有趣的恒等式.     

关于Smarandache函数的一个问题

对任意正整数n,著名的Smarandache函数S(n)定义为最小的正整数m使得n|m!.即就是S(n)=min{m:m∈N,n|m!}.令PS(n)表示区间[1,n]中S(n)为素数的正整数n的个数.在一篇未发表的文献中,J. Castillo建议我们研究当n→∞时,比值PS(n)/n的极限存在问题.如果存在,确定其极限.本文的主要目的是利用初等方法研究这一问题,并得到彻底解决!即就是证明该极限存在且为1.     

Smarandache函数的几类相关方程的解

设φ(n),S(n)分别表示正整数n的Euler函数和Smarandache函数,利用初等的方法和技巧,依据Smarandache函数计算公式,给出k的方程φ(p~αm)=S(p~(ακ))的所有解,其中p为素数,α,m为正整数且gcd(m,p)=1,由此得到方程φ(n)=S(n~k)的所有解(n,k)进而确定了满足条件S(n)|σ(n)的全部正整数n.最后,根据莫比乌斯变换反演定理证明了方程φ(n)=∑_(d|n)S(d)仅有两个解,分别为n=2~5和n=3×2~5.     

一个关于原数函数Sp(n)的恒等式

对于任意给定的素数p及正整数n,我们定义幂p的原数函数Sp(n)为最小的正整数m使得pn|m!.即就是:Sp(n)=min{m:pn|m!}.本文的主要目的是利用初等方法研究函数Sp(n)的算术性质,并得到一个有趣的恒等式.     

关于伪Smarandache函数的一个问题

对任意正整n,著名的伪Smarandache函数Z(n)定义为最小的正整数m使得n|m(m 1)/2.本文的主要目的是利用初等方法研究Kenichiro Kashihara提出的"求所有正整数n使得伪smarandache函数Z(n)为n的原根"这一问题,并得到彻底解决.即就是证明了Z(n)为n的原根当且仅当n=2,3,4.     

函数Sp(n2)与Sp(n)的关系

对于任意正整数n,设幂p的原数函数Sp(n)定义为Sp(n)=min{m:pn|m!},其中p为素数.本文目的是运用初等方法研究函数Sp(n2)与Sp(n)之间的关系,并得到一个有趣的恒等式.     

RECENT PROGRESS ON SPHERICAL HARMONIC APPROXIMATION MADE BY BNU RESEARCH GROUP ——In memory of Professor Sun Yongsheng

As early as in 1990, Professor Sun Yongsheng, suggested his students at Beijing Normal University to consider research problems on the unit sphere. Under his guidance and encouragement his students started the research on spherical harmonic analysis and approximation. In this paper, we incompletely introduce the main achievements in this area obtained by our group and relative researchers during recent 5 years （2001-2005）. The main topics are： convergence of Cesaro summability, a.e. and strong summability of Fourier-Laplace series; smoothness and K-functionals; Kolmogorov and linear widths.     

A unified approach to certain problems of best local approximation

In this paper we study best local quasi-rational approximation and best local approximation from finite dimensional subspaces of vectorial functions of several variables. Our approach extends and unifies several problems concerning best local multi-point approximation in different norms.     

Boundedness for commutators of multipliers on Hardy type spaces

In this paper, we study the commutators generalized by multipliers and a BMO function. Under some assumptions, we establish its boundedness properties from certain atomic Hardy space Hb^p（R^n） into the Lebesgue space L^p with p 〈 1.     

THE 8~(th) INTERNATIONAL CONGRESS ON INDUSTRIAL AND APPLIED MATHEMATICS

<正>August 10-14,2015Beijing,ChinaThe International Congress on Industrial and Applied Mathematics(ICIAM)is the premier international congress in the field of applied mathematics held every four years under the auspices of the International Council for Industrial and Applied Mathematics.From August 10 to 14,2015,mathematicians,scientists     

Towards Excellence in Science Chinese Academy of Sciences

<正>May 26,2014,Beijing Science is a human enterprise in the pursuit of knowledge.The scientific revolution that occurred in the 17th Century initiated the advances of modern science.The scientific knowledge system created by     

Bounds for the zeros of polynomials

Let P(z)=∑↓j=0↑n ajx^j be a polynomial of degree n. In this paper we prove a more general result which interalia improves upon the bounds of a class of polynomials. We also prove a result which includes some extensions and generalizations of Enestrǒm-Kakeya theorem.     

Boundedness of commutators related to Marcinkiewicz integrals on hardy type spaces

In this paper, the authors study the boundedness of the operator [μΩ, b], the commutator generated by a function b ∈ Lipβ(Rn)(0 ＜β≤ 1) and the Marcinkiewicz integrals μΩ, on the classical Hardy spaces and the Herz-type Hardy spaces in the case Ω∈ Lipα(Sn-1)(0 ＜α≤ 1).     

Jacobi polynomials used to invert the laplace transform

Given the Laplace transform F(s) of a function f(t), we develop a new algorithm to find an approximation to f(t) by the use of the classical Jacobi polynomials. The main contribution of our work is the development of a new and very effective method to determine the coefficients in the finite series expansion that approximation f(t) in terms of Jacobi polynomials. Some numerical examples are illustrated.     

Generalization of the interaction between Haar approximation and polynomial operators to higher order methods

In applications it is useful to compute the local average empirical statistics on u. A very simple relation exists when of a function f（u） of an input u from the local averages are given by a Haar approximation. The question is to know if it holds for higher order approximation methods. To do so, it is necessary to use approximate product operators defined over linear approximation spaces. These products are characterized by a Strang and Fix like condition. An explicit construction of these product operators is exhibited for piecewise polynomial functions, using Hermite interpolation. The averaging relation which holds for the Haar approximation is then recovered when the product is defined by a two point Hermite interpolation.