#include <bits/stdc++.h>

using namespace std;

long sumOfGroup(long long k) {
    long long last=(k*(k+1));
    long long fir =(k*(k-1));
    return (k*k*((k+1)*(k+1)-(k-1)*(k-1)))/4;
}

int main() {
    int k;
    cin >> k;
    long answer = sumOfGroup(k);
    cout << answer << endl;
    return 0;
}