Powers of 3 having the same digits

rearrange_power_of_three.py

"""
James Tanton @jamestanton asked:
Is there a power of three whose digits can be rearranged to form 
another power of three?
(https://twitter.com/jamestanton/status/676773021223272448)

The following Python script searches for examples. There is no power
of three, less than 3^200000, whose digits can be rearranged to form
another power of three.
"""

from itertools import count

def digits(n):
    return sorted(str(n))

power_of_3 = 1
digits1 = digits2 = None
digits3 = digits(power_of_3)

for n in count(1):
    power_of_3 *= 3
    digits1 = digits2
    digits2 = digits3
    digits3 = digits(power_of_3)
    if digits1 == digits3:
        print n-2, n
        break
    if digits2 == digits3:
        print n-1, n
        break