More Series

#include <stdio.h>

int main() {

    int  i, n;
    double sum;

    n = 1000;
    sum = 0.0;

    for (i = 1; i <= n; i=i+1)
          sum = sum + 1/((double)i*(double)i);

    printf("Sum of %d terms is %lf\n",n,sum);

}

#include <stdio.h>

int main() {

    int  i, n;
    double x, sum;

    n = 1000;
    sum = 0.0;

    for (i = 1; i <= n; i=i+1){
          x = 1/(double)i;
          sum = sum + x*x*x;
}
    printf("Sum of %d terms is %lf\n",n,sum);

}