#include <bits/stdc++.h>
using namespace std;
int main() {
  unsigned long long x;
  cin >> x;
  if (x == 1)
    cout << x * 2 << endl;
  else {
    long long sum = 0;
    for (long long i = 1; i <= x; i++) {
      sum += pow((long long)2, i);
    }
    cout << sum << endl;
  }
}
