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