#include<fstream.h>
#include<math.h>

int n,c,i,j;

int main()
{  ifstream fin("fractii.in");
   ofstream fout("fractii.out");
   fin>>n;
   c=0;
   for(i=2;i<=n;i++)
		for(j=2;j<=n;j++)
		{	if(i%j==0) c++;
				else
				if(j%i==0) c++;
		}
   fout<<(int)pow(n,2)-c;
   fin.close();
   fout.close();
   return 0;
}