Thirteenth floor

Normally, elevator buttons are numbered one by one. However, at least in the United States, for superstitious reasons, people like to make the elevator buttons go directly from 12 to 14. Note that although it is very popular to say "There is no thirteenth floor" or "This building has a twelfth floor and a "14th" floor but no thirteenth floor", this is really not correct, because "thirteenth" properly means "next after the twelfth", not "numbered 13", and so there IS a thirteenth floor, it's just numbered "14".

It was used as a leitmotif in a late Fassbinder movie.