#include<bits/stdc++.h> using namespace std; long long a[51]; int main(){ int n; cin >> n; a[1] = 1; a[2] = 2; for(int i = 3;i <= n;i++){ a[i] = a[i-1]*2; } long long ans = 0; for(int i = 1;i <= n;i++){ ans = ans+a[i]; } cout << ans; return 0; }