program fractii;
var n,i,k:integer;
    f,g:text;
begin
	assign(f,'fractii.in');
	assign(f,'fractii.out');
	reset(f);
        rewrite(g);
	readln(f,n);
	k:=0;
	for i:=1 to n do
		for j:=1 to n do
			if i mod j<>0 then
				k:=k+1;
	write(g,k);
	close(f);
	close(g);
end.