#include <stdio.h>

 void  fun(int n)
{
 int i,j;
 long int sum=0,temp;
 for(i=1;i<n;i++)
 {  temp=0;
  for(j=1;j<=i;j++)
    temp+=j;
	
	sum+=temp; 
	}
  printf("%d,%d\n",n,sum);
}

 void  main()
 {
 int n;
 printf("please input a number to n:");
 scanf("%d",&n);
 if(n<1)
 {
 printf("The n must be to than 1!");
   return ;
 }
  fun(n);
 }