Solution to puzzle 22

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 The question was

Find a number such that it is divisible by 9, and when we remove the right most digit, it will be divisible by 8. When you remove the next right most digit, it will be divisible by 7. And so on. 

ABCDEFGHI should be divisible by 9

ABCDEFGH must be divisible by 8

ABCDEFG must be divisible by 7 and so on until

AB must be divisible by 2

A must be divisible by 1. 

And the solution:

381654729


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