1. The problem statement, all variables and given/known data http://img512.imageshack.us/img512/9990/untitledsm9.png [Broken] 2. Relevant equations The permutation & combinations equation? I don't quite know how to type them out in here, but there's the calculator :rofl: 3. The attempt at a solution Since the maximum number of integers a value can have would up up to 1000000000, there would a total of 1digit+2digit + 3digit+...+8digit numbers +9 digit numbers altogether. 10 digit numbers don't count as the last number would be 0. For the 9 digit nos, it would be just 123456789 which is 1 way, 8 digit: 12345678 or 23456789, but as the digits get smaller I'm confused and at a loss to what to do. Any help would be greatly appreciated.