var f,g:text;
    i,j,n,q:longint;
    r:longint;
begin
 assign(f,'fractii.in');
 assign(g,'fractii.out');
 reset(f);
 rewrite(g);
 readln(f,n);
 close(f);


 for i:=2 to n do begin
  for j:=2 to n do
   if (i mod j <> 0) and (j mod i <> 0 ) then
    if i < j then r:=r+2;

 end;
  r:=r+n*2;
  writeln(g,r-1);
 close(g);
end.