#include <stdio.h>

int main()
{
   int n,i;
   double e,sum=2.0;

   printf("n e\n");
   printf("- -----------\n");
   printf("0 1\n");
   printf("1 2\n");
   printf("2 2.5\n");
   for (n=3,e=2.5;n<=9;n++){
      sum*=n;
      e+=1/sum;
      printf("%d %.9lf\n",n,e);
   }

   return 0;    
}