## Enter derangement

##### How does the Derangements - Subfactorials Calculator work?
Free Derangements - Subfactorials Calculator - Calculates the number of derangements/subfactorial !n.
This calculator has 1 input.

### What 1 formula is used for the Derangements - Subfactorials Calculator?

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

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##### What 7 concepts are covered in the Derangements - Subfactorials Calculator?
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.
nPr = 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