#include <fstream>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
int n;
void citire(int&n)
{f>>n;}
int a;
int euler(int a)
{int r,b,aux1=a,aux,nr=0,aux2;
 for(b=1;b<=n;b++)
 {aux2=b;
  if(a<b)
   {aux=a;
    a=b;
    b=aux;
   }
  r=a%b;
  while(r)
  {a=b;
   b=r;
   r=a%b;
  }
  if(b==1)nr++;
  a=aux1;
  b=aux2;
 }
 return nr;
}
void fractii(int n)
{int a,nr=0;
 for(a=1;a<=n;a++)nr=nr+euler(a);
 g<<nr;
}
int main()
{citire(n);
 fractii(n);
    return 0;
}