通过对数列的分析可知:ai=2(i=1)ai=1+1/ai-1(i>=2)
#include<stdio.h>
int main()
{
int i , n;
double sum,item;
scanf("%d",&n);
sum=0;
item=2;
for(i=1;i<=n;i++)
{
sum=sum+item;
item=1.0+1.0/item;
}
printf("The sum of sequences is %f",sum);
return 0;
}