#include <bits/stdc++.h>
using namespace std;

int main() {
    int x;
    cin >> x;
    vector<long double> zeta(10001, 1);
    for(int i=2;i<10001;i++) {
        for(int j=2;j<100000;j++) {
            long double nxt = zeta[i] + (long double)1 / powl(j, i);
            if(nxt - zeta[i] < 1e-200) break;
            else zeta[i] = nxt;
        }
    }

    long double out = 0;
    for(int i=x;i<10001;i++) {
        out += zeta[i] - 1;
    }

    out *= 1e6;

    out = floor(out);

    cout << out << '\n';
}