1/(123),1/(345),......1/((2n-1)(2n)(2n+1)),......

来源：百度知道编辑：UC知道时间：2024/04/29 00:15:56

不知道你要什么语言，我就用C把
#include<stdio.h>
const int n=100;
main()
{
double a=0,b,i,j;
for(i=1;i<n;i++)
{
b=1;
for(j=1;j<=i;j++)
b*=j;
a+=1/b;
}
printf("%lf\n",a);
getch();
}

..你想问什么?

1+1/(1+2)+1/(1+2+3)+...+1/(1+2+3+...+100) 1+1/(1+2)+1/(1+2+3)+-------+1/(1+2+3+----+100) (1/2005-1)(1/2004-1)........(1/3-1)(1/2-1) 1+1/1+2+1/1+2+3+...+1/1+2+3...+2000 1*(1/1+2)*(1/1+2+3)*~~~*(1/1+2+~~~2005)=? 1+1/2+1/3+.....+1/n 1+1/2+1/3+...+1/100 1-1/2+1/3-.....-1/10 (1+1/2+1/3+1/4)× 1/1+2 + 1/1+2+3 +....+ 1/1+2+3+....+100=

1/(1*2*3),1/(3*4*5),......1/((2n-1)(2n)(2n+1)),......

1/(123),1/(345),......1/((2n-1)(2n)(2n+1)),......