#include<bits/stdc++.h>
using namespace std;
int f(int n){
	int r;
	if(n==1)
		return 1;
	return (f(n-1)+1)*2-1;
}
int main(){
	int n;
	cin>>n;
	cout<<f(n); 
return 0;}

/**************************************************************
	Problem: 1223
	User: fzy001
	Language: C++
	Result: Accepted
	Time:7 ms
	Memory:2072 kb
****************************************************************/