#include<fstream.h>
main()
{long n,k,j,cont=0,auxk,auxj,c;
 ifstream i("fractii.in");
 ofstream o("fractii.out");
 i>>n;cont=2*n-1;
 if(n%2==0)
   cont=cont+n-2;
  else
   cont=cont+n-1;
 for(k=3;k<=n;k++)
   for(j=3;j<=n;j++)
    {auxj=j;auxk=k;
     do
      {c=auxk%auxj;
       auxk=auxj;
       auxj=c;
      }while(c!=0);
     if(auxk==1)
      cont++;
    }
 o<<cont<<'\n';
 i.close();
 o.close();
 return 0;
}