There are a large number of 9 digit integers in the range 123456789 to 987654321 where each digit only appears once.
Your mission should you choose to accept is to identify the 100,000th number in this sequence.
The first number is the easiest to find - 123456789, the second is 123456798, the third is 123456879 and so on. No digit may repeat so 122345675 is not a valid number in this sequence.