I don't know much about Illinois except for an airplane switch in O'Hare, but in the rest of America the underlined 23 would mean 23 repeating after the 10. Until Aikiweb gets superscript, exponents will be written with the carrot (^). I will not tolerate insolence. If you were making a joke, I think I get it. Thanks for actually paying attention with me in chemistry. This number was drilled into my mind. We even had a "mole day" and Tootsie "mole" pops were distributed about the classroom. It still baffles me that my warm hearted, though extremely fascist chem teacher lets us have candy during class!
Ahh, you must see it as Michael Jordan's number! :-b