#include<fstream.h>
ifstream f("fractii.in");
ofstream g("fractii.out");
int  euclid(int a, int b)
{int c;
 while(b)
      {c = a % b;
       a = b;
       b = c;
       }
 return a;}
int main()
{unsigned long n,i,j,fr=0;
 f>>n; fr=2*n-1;
 for(i=2;i<=n;i++)
    for(j=2;j<=n;j++)
	if(i!=j&&euclid(i,j)==1)
	   fr=fr+1;
 g<<fr;
 return 0;}