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Pandigital multiples

Problem 39 →

Pandigital multiples

Problem 38

Take the number 192 and multiply it by each of 1, 2, and 3:
192 × 1 = 192
192 × 2 = 384
192 × 3 = 576
By concatenating each product we get the 1 to 9 pandigital, 192384576. We will call 192384576 the concatenated product of 192 and (1,2,3)
The same can be achieved by starting with 9 and multiplying by 1, 2, 3, 4, and 5, giving the pandigital, 918273645, which is the concatenated product of 9 and (1,2,3,4,5).
What is the largest 1 to 9 pandigital 9-digit number that can be formed as the concatenated product of an integer with (1,2, ... , n) where n > 1?
from tools import is_pandigital


def find_all():
    # Range 9200 - 9400 found using trial&error
    for y in range(9200, 9400):
        x = str(y) + str(2 * y)
        if is_pandigital(x):
            yield x


def run():
    return list(find_all())[-1]