#include<fstream.h>

ifstream f("fractii.in");
ofstream g("fractii.out");

long N,nr;


int main()
{
  f>>N;  f.close();

  for(long i=2;i<N;i++)

   for(long j=i+1;j<=N;j++)

   { long a=i; long b=j;

     while(a!=b)

      if(a<b) b=b-a;

       else a=a-b;

     if(a==1) nr=nr+2;
   }


  g<<nr+N+N-1;  g.close();

  return 0;
}