@atmathlab: This isn’t a typo… those multiple exclamation marks actually mean something 😳 It’s called a multi-factorial. Most people know factorial: n! means you multiply every number down to 1. Example: 5! = 5 × 4 × 3 × 2 × 1 = 120 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… Examples: 6!! = 6 × 4 × 2 = 48 (you skip every other number) 7!!! = 7 × 4 × 1 = 28 (you go down by 3 each time) 10!!!! = 10 × 6 × 2 = 120 (you go down by 4 each step) 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. #math #mathtok #mathematics