#include <bits/stdc++.h>
using namespace std;
const long double pi = 3.1415926536;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int n;
  cin >> n;
  unsigned long long int out = 0;
  for (int i = 1; i <= n; i++) {
    out += (unsigned long long int)1 << i;
  }
  cout << out << endl;
  return 0;
}
