#include <iostream>
#include <cmath>
int main()
{
int k = 0;
float x, res = 0;
std::cin >> x;
while (++k <= 8)
res += pow(log(x + 1), 1 / k);
std::cout << res;
}
#include <iostream>
#include <cmath>
int main()
{
int k = 0;
float x, res = 0;
std::cin >> x;
while (++k <= 8)
res += pow(log(x + 1), 1 / k);
std::cout << res;
}