#include <stdio.h>
#define M 1000000007
int main ()
{
   long long n,a;
   scanf("%lld",&n);
   a=n-1;
   long long sum = 0;
   for(long long i=1;i<=a;i++){
        sum+=(i*(a-i+1)*(a-i+1))%M;
   }
   sum=(sum%M+M)%M;
   printf("%lld",sum%M);
   return 0; 
}