# include <fstream.h>
using namespace std;
int main ()
{
long c=0,n,i,j;
fstream f("fractii.in", ios::in);
fstream t("fractii.out",ios::out);
f>>n;
for (i=1;i<=n;i++)
	for (j=1;j<=n;j++)
			{
			if (i/j!=0)
			c++;
			}
t<<c+1;
return 0;
}