#include <bits/stdc++.h>
using namespace std;
int main(){
int a,b=0;
cin>>a;
int e=0;
while(a>=1){
e=a*a;
b=e+b;
a--;
}
cout<<b;
}
/**************************************************************
Problem: 1054
User: toughuatao1
Language: C++
Result: Accepted
Time:14 ms
Memory:2072 kb
****************************************************************/