#include
#include
using namespace std;
double k(double x, int n, int i) {
return pow(x, n) - pow(x, i);
}
double s(double x, int n) {
double sum = 0.0;
for (int i = 1; i <= n; ++i) {
double a = i - 1;
sum += (i * i + x) * (k(x, n, i) + a / pow(x, a));
}
return sum;
}
int main() {
double x = 0.1;
int n = 38;
double y = s(x, n);
cout << "S(x, N) = " << y << '\n';
}