摘要
对任意正整数n,定义一个与著名的F.Smarandache函数的对偶函数密切相关的数论函数S**(n)如下:S**(n)={max{2m:m∈N*,(2m)!!|n},如果n为偶数;max{(2m-1):m∈N*,(2m-1)!!|n},如果n为奇数.利用初等方法,运用关于ln([x]!)的渐近公式和sinnx的定积分与n!!的关系以及一些特殊幂级数收敛的性质,通过对正整数n按奇偶性分类讨论,研究了函数S**(n)的均值性质,并给出一个较强的渐近公式:对任意实数x>1,有∑n≤xS**(n)=x.〔2e^(1/2)-3+2e^(1/2)∫01e^(-y2/2)dy〕+O(ln^2x),其中e=2.718281828459…为常数。
For any positive integer n, a number theoretic function S ^** (n) relating to Smarandache dual function is defined as follows:S^**(n)={max{2m:m∈N^*,(2m)!!|n},max{(2m-1):m∈N^*,(2m-1)!!|n}.The mean value properties of S ^** (n) is studied by using the elementary methods, that is, applying the asymptotic formula of In ( [ x ] ! ) and the relationship between integration of sin^n x and n !!, as well as certain properties of power series, and classify positive integer n into even and odd. Moreover, a sharper asymptotic formula about the sum of S ^** (n) is given by ∑n≤x S^**(n)=x·(2e^1/2-3+2e^1/2∫0^1 e^-y2/2dy)+Oln^2x,arbitary x〉1,where e =2. 718 281 828 459....
出处
《黑龙江大学自然科学学报》
CAS
北大核心
2008年第3期340-342,346,共4页
Journal of Natural Science of Heilongjiang University
基金
国家自然科学基金资助项目(10671155)
关键词
数论函数
均值
渐近公式
number theoretic function
mean value
asymptotic formula