concat = str(n)

for i in itertools.count(2):

concat += str(n*i)

if len(concat) == 9 and is_pandigital(int(concat)): return int(concat)

"""http://projecteuler.net/index.php?section=problems&id=38

What is the largest 1 to 9 pandigital that can be formed by multiplying a

fixed number by 1, 2, 3, ... ?"""