@iq.psychology: This isn't a typo... those multiple exclamation marks actually mean something It's called a multi-factorial. Most people know factorial: !! means you multiply every number down to 1. But with multi-factorials, you don't go down by 1... You skip numbers. The number of exclamation marks tells you the step: !! → skip by 2 !!! → skip by 3 !!!! → skip by 4 and so on... So instead of multiplying everything, you only multiply numbers that follow that pattern. Think of it like: You're going down a staircase... but you're jumping multiple steps at a time. That's why it looks confusing — but once you see the pattern, it's actually simple. #iq #iqtest #mathmemes