C++ :

#include<iostream>
#include<cstdio>
using namespace std;

int N,ans;

int main()
{
//	freopen("ap.in","r",stdin);
//	freopen("ap.out","w",stdout);	
    cin >>N;
    ans=2;
	for (int i=1; i<N; i++)
	{
		ans = (ans+1)*2;
	}
    cout << ans<<endl;
	return 0;
}