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# ###
# 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?
# ###
import itertools
def is_palindrom(s):
return len(s) == 9 and ''.join(sorted(s)) == '123456789'
largest = 0
for n in range(1, 987654321):
results = []
for mul in itertools.count(1):
results.append(n * mul)
str_res = ''.join([str(x) for x in results])
res = int(str_res)
if is_palindrom(str_res) and res > largest:
largest = res
print(largest)
if res > 987654321:
break
print(largest)
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