#include <bits/stdc++.h>
const long long mod = 1000000007;
using namespace std;
int n, m;
vector<vector<int> > graf;
vector<int> dp;
int main() {
  long long n;
  cin >> n;
  long long ans = 0;
  while (n) {
    ans += (long long)pow(2, n);
    n--;
  }
  cout << ans;
  return 0;
}
