program p_003;{fractii}
var n,p,q,nr:longint;
begin
  assign(input,'fractii.in'); reset(input);
  assign(output,'fractii.out'); rewrite(output);
  readln(n);
  nr:=n;
  for p:=2 to n do begin
    nr:=nr+1;
    for q:=2 to n do begin
      if (p mod q<>0) and (q mod p<>0) then nr:=nr+1;
    end;
  end;
  write(nr);
  close(input); close(output);
end.