Python | sympy.subfactorial() method

With the help of sympy.subfactorial() method, we can find the Subfactorial of a number in SymPy. Subfactorial of a number is given by –

Syntax: subfactorial(n) Parameter: n – It denotes the number whose subfactorial is to be calculated. Returns: Returns the subfactorial of number, i. e., n.

Example #1:

# import sympy
from sympy import *

n = 4
print("Value of n = {}".format(n))

# Use sympy.subfactorial() method
subfactorial_n = subfactorial(n)

print("Subfactorial of n : {}".format(subfactorial_n))

Output:

Value of n = 4
Subfactorial of n : 9

Example #2:

# import sympy
from sympy import *

n = 9
print("Value of n = {}".format(n))

# Use sympy.subfactorial() method
subfactorial_n = subfactorial(n)

print("Subfactorial of n : {}".format(subfactorial_n))

Output:

Value of n = 9
Subfactorial of n : 133496