#include <iostream>
#include <assert.h>
#define rep(i,n) for(int i=0; i<(int)(n); i++)

using namespace std;
using LL = long long;
const LL INF = 1e12;

const int Max_x = 1e4;
const int Max_a = 1e6;

double zeta(LL a, LL x){
  LL res = a - 1;
  rep(i,x - 1){
    res *= a;
    if(res > INF) break;
  }
  double d = res;
  return 1 / d;
}

int main(){
  LL x;
  cin >> x;
  assert(2 <= x and x <= Max_x);
  double res = 0.0;
  if(x == 2){
    cout << 2000000 << endl;
  }
  else{
    for(LL a = 2; a <= Max_a; a++) res += zeta(a, x);
    res *= 1000000;
    int ans = res;
    cout << ans << endl;
  }

  return 0;
}