I'd still ask for the definition of factorial. Sure, for various reasons, most programmers know the factorial, but I'd consider remembering the definition of s

I'd still ask for the definition of factorial. Sure, for various reasons, most programmers know the factorial, but I'd consider remembering the definition of some mathematical operation only common in certain domains (statistics and finance?), that most people only learn in high school and never use again, to be rote memorization.