Near the end of the show, Jackie says of the "two nots", ". . .they're not green or not a creature. . ." They are, in fact, not green and not creatures. It would ordinarily be a minor flub, but since one of the major concepts of this episode is the difference between "or" and "and", it's a very annoying error.
Matt's Girl Edit:Either way you slice it,the show's still funny,even IF the logic can be off sometimes! Even math geniuses make mistakes!