var     n,s,i,j:longint;
        f:text;
begin
  assign(f,'fractii.in');
  reset(f);
  read(f,n);
  close(f);

  s:=2*n-1;
  for i:=2 to n do
  for j:=1 to n do
  if (((i mod j)<>0) and ((j mod i)<>0)) then inc(s);


  assign(f,'fractii.out');
  rewrite(f);
  write(f,s);
  close(f);
end.