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