A math prof of mine would label insufficient initialization in recursive proofs with i.i. (it also stood for a few other common mistakes, such as “incorrect int

A math prof of mine would label insufficient initialization in recursive proofs with i.i. (it also stood for a few other common mistakes, such as “incorrect integration” or whatever). And he would invariably add “i.i = -1”, which was the penalty for such mistakes (exams being graded out of 20). A deliciously nerdy joke, unless you’re on the receiving end.