#include <bits/stdc++.h>
using namespace std;
signed main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long n;
  cin >> n;
  long long ans = 0;
  long long x = 2;
  for (long long i = 1; i <= n; ++i) {
    ans += x;
    x *= 2;
  }
  cout << ans;
  return 0;
}
