My first encounter with a DEC-20 was MACLISP for an AI class.  Of course, the first thing you write is factorial, but I forgot the termination condition. Before I figured out why it was taking so long and send a brk, my CPU quota for the semester got consumed and TOPS kicked me off and locked me out.  Luckily the dept secretary took pity and gave me some more time.<p>We also had APL for a numerical methods class on that system. Yes, we had some terminals with the special APL symbols; I think they were  LA-36&#x27;s.<p><a href="http:&#x2F;&#x2F;www.columbia.edu&#x2F;cu&#x2F;computinghistory&#x2F;la36.html" rel="nofollow">http:&#x2F;&#x2F;www.columbia.edu&#x2F;cu&#x2F;computinghistory&#x2F;la36.html</a>