Representation of the formula P(n) = (n!)(6^n)
No reason not to make this into a function so it accepts any n.

from math import factorial

def p_of_n(n):
    return factorial(n) * 6**n


Usage:

p_of_n(156)
# output
# 18406764427683965418916585176958885211344286062729194034218082474442355263185795072343804159971536825774135674029142847535155218179997173513194885826708904869034790974161877000771825382336273724208349735310762691458714078255765145189212114617969848727557053656769497332473231995332585780414682079382672173143342192602090273021078801460026695582968493824697958400000000000000000000000000000000000000