#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i,m,n) for(int i=m; i<n; ++i)
#define repl(i,m,n) for(ll i=m; i<n; ++i)

int main(){
    ll N;
    cin >> N;

    ll ans = 0LL;
    repl(i, 1, N+1){
        if(i % 3LL == 0LL) ans += i*i*i;
        else if(i % 3LL == 1LL) ans += i;
        else ans += i*i;
    }
    cout << ans << endl;

    return 0;
}