#include<bits/stdc++.h>
using namespace std;
int main(){
	int n,s=0;
	cin>>n;
	for(;n>=1;n--){
		s=s+n*n;
	}
	cout<<s;
}

/**************************************************************
	Problem: 1054
	User: zengyixuan
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/