var f,g:text;
    P,Q,N,a,b:longint;
    k:real;
 begin
  assign(f,'fractii.in');
  assign(g,'fractii.out');
   reset(f);
   rewrite(g);
    read (f,N);
    k:=0;
     for P:=1 to N-2 do
      for Q:=P+1 to N do 
       begin
       a:=P;
       b:=Q;
        while (a<>b) do
           if (a<b) then b:=b-a
                    else a:=a-b;
        if (a=1)and(b=1) then k:=k+1;
      end;  
      k:=2*k+1;
    write (g,k:0:0);
    close(f);
    close(g);
     end.