To better understand multiple recursion. Recursion keeps "stacks" of numbers, in this case 5, 4, 3, 2, but if any of those doesn't meet this case's criteria, If n > 2, then the number in the stack is knocked off the stack. The stack is like a list. The function which I named "subtract" makes "recursive calls to the stack." This might help us understand how recursion can elegantly make trees and fractals.
The "add n to list of ns" is only to show us what is happening. That list is not necessary. The recursion keeps it's own internal list called a "stack." The recursive function "subtract" starts with n = 5 if n > 2 set n to n - 1 --> 5, 4, 3, 2 (numbers in a stack) since 2 is not > 2, code knocks "2" off the stack but then goes to set n to n - 2 starting with "3" (the number at top of stack) so 3 - 2 is 1 ... then goes to set n to n - 3 I based this on a u tube tutorial (although that used C++): youtube ?v=0nKIr3kAt-k
