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#include<bits/stdc++.h>
using namespace std;
long long p[1005];
int main(){
long long n;
cin >> n;
p[1] = 1;
p[2] = 5;
p[3] = 9;
for(int i = 4;i <= n;i++) p[i] = p[i-1] * 2 - 1;
cout << p[n];
return 0;
}