C++ :

#include <stdio.h>
#include <string.h>

int n;

int main(){
	//freopen("data.in","r",stdin);
	//freopen("data1.out","w",stdout);
	while(scanf("%d",&n) != EOF){
		/*int m = n+1;
		int ans = 0;
		for(int i = 0; i <= n; i++){
			if(i == 0) ans += m * (m-1) / 2;
			else ans += m * (m-1);
			m -= 1; 
		}
		printf("%d\n",ans);*/
		 
		// sigma(n^2);
		printf("%d\n",n*(n+1)*(2*n+1)/6);
	}
	return 0;
}