> I consider backslashes to be very ugly. I'd prefer the empty > set to be "0" (or if it has to be distinguished from 0 for > typing reasons: "empty") and the #238 to be "in". > I think Freek is absolutely right! mailto:kolany@ux2.math.us.edu.pl http://ux1.math.us.edu.pl/~kolany/adam.htm