Maybe with numbers it would be easier to understand.
If there is 1 insert to the list 5
If there is a 5 insert to the list 6 or 4
So if i start from 1 one possible list would be: {1, 5, 6}
ahha, i have 64 bit windows, but running rhino 4 32 bit, hoping to get the 64bit rhino 5 soon, does gh works in rhino5 as well?? thanks for the info david!