#include <bits/stdc++.h>

#define ll long long
#define endl "\n"
#define __count __builtin_popcount
#define yes cout<<"Yes\n";
#define no cout<<"No\n";
using namespace std;

void solve() {
    ll n;cin>>n;
    if(n==1){
        cout<<1<<endl;
        return;
    }
    ll d=4;
    ll a[n+1];
    a[2]=1;
    ll now=2;
    ll gt=1;
    ll i;
    a[3]=3;
    for(i=4;i<=n;i++){
        a[i]=a[i-1]+pow(2,now)+2;
//        cout<<i<<" "<<a[i]<<endl;
        now+=3;
    }
    cout<<a[n]<<endl;
}

signed main() {
#ifdef ONLINE_JUDGE
#else
    freopen("114514.in", "r", stdin);
    freopen("114514.out", "w", stdout);
#endif

    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    ll t = 1;
//    cin >> t;
    while (t--)
        solve();
}