#include <bits/stdc++.h>
using namespace std;
int main() {
  vector<long long> dp(56, 0);
  dp[1] = 2;
  for (long long i = 2; i < 56; i++) {
    dp[i] = dp[i - 1] + (pow(2, i));
  }
  dp[55] -= 2;
  long long n;
  cin >> n;
  cout << dp[n];
  return 0;
}
