There are a limited number of iterations that can occur
The sequence will progress from 0 upwards in multiples of 9 (e.g 0, 9,18,27 etc)
What is clever is that the symbol against 0 and each multiple of 9 is the same on each go, but it changes each new go, so you believe that something weird is going on.
The reality is that your answer is always going to be 0 or a multiple of 9. The symbol changes on each iteration.
