the first iteration is the starting input. the second iteration, starting at 2, is 2 1. (if we had started at 5, the sequence would be 5 4 3 2 1.) the third iteration, starting at 3 is: 3 2 1 followed by 2 1 followed by 1, or a three dimensional pyramid (the numbers represent height) the fourth iteration starting at four is 4321-321-21-1 321-21-1 21-1 1 or a four dimensional pyramid.
breaks quite bad when you add fractional numbers as the script that checks when to stop "pyramiding" has to end at exactly zero. the script waits until the number (which is fractional) to reach zero, which it never will since it will go negative. hope there can be a formula to generalize the sum of each number for any iteration count and starting value