Calculate !5
Derangements are a permutation where
No original set elements
appear in their same position
Derangements formula for !n:
!n = [n!/e + 0.5]
where [] is the floor function
and e = Eulers constant of 2.718281828459
Plugging in our numbers, we get:
!5 = [5!/2.718281828459 + 0.5]
Calculate 5!
5! = 5 x 4 x 3 x 2 x 1
5! = 120
!5 = [120/2.718281828459 + 0.5]
!5 = [44.145532940573 + 0.5]
!5 = [44.645532940573]
[44.645532940573] = 44
!5 = 44
