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sin^n x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≤x S^**(n)=x·(2e^1/2-3+2e^1/2∫0^1 e^-y2/2dy)+Oln^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....