Free Derangements - Subfactorials Calculator - Calculates the number of derangements/subfactorial !n.

This calculator has 1 input.

This calculator has 1 input.

!n = [n!/e + 0.5] where [] is the floor function and e = Eulers constant of 2.718281828459

For more math formulas, check out our Formula Dossier

For more math formulas, check out our Formula Dossier

- derangement
- permutation with no fixed points

!n - derangements - subfactorials
- euler
- Famous mathematician who developed Euler's constant
- factorial
- The product of an integer and all the integers below it
- floor
- the greatest integer that is less than or equal to x
- permutation
- a way in which a set or number of things can be ordered or arranged.
_{n}P_{r}= n!/(n - r)! - subfactorial
- calculate the number of permutations of a set of n objects in which none of the elements occur in their natural place

!n