#include <fstream.h>
int main()
{ int i,j,fr,x,y,r;
long n;
ifstream f("fractii.in");
ofstream g("fractii.out");
f>>n;
fr=1;
for (i=1;i<n;i++)
 for (j=i+1;j<=n;j++)
  {x=i;
   y=j;
   do {
   r=x%y;
   x=y;
   y=r;
   } while (r=0);
   if (x=1) fr+=2;
   }
g<<fr;
f.close();
g.close();
}