scipy.misc.factorialk

scipy.misc.factorialk(*args, **kwds)

factorialk is deprecated! Importing factorialk from scipy.misc is deprecated in scipy 1.0.0. Use scipy.special.factorialk instead.

Multifactorial of n of order k, n(!!…!).

This is the multifactorial of n skipping k values. For example,

factorialk(17, 4) = 17!!!! = 17 * 13 * 9 * 5 * 1

In particular, for any integer n, we have

factorialk(n, 1) = factorial(n)

factorialk(n, 2) = factorial2(n)

Parameters

nint

Calculate multifactorial. If n < 0, the return value is 0.

kint

Order of multifactorial.

exactbool, optional

If exact is set to True, calculate the answer exactly using integer arithmetic.

Returns

valint

Multifactorial of n.

Raises

NotImplementedError

Raises when exact is False

Examples

>>> from scipy.special import factorialk
>>> factorialk(5, 1, exact=True)
120L
>>> factorialk(5, 3, exact=True)
10L