** Note.** For every positive integer **n**, the
* Lothar Collatz function* is defined by

(**Click the Maple
icon below to see the graph of the Collatz function stopping time
function, i.e. how many iterations it takes to reach 1. The
Maple code was kindly provided by Gaston Gonnet; see his article
in the Maple Tech Newsletter Issue 6, Fall 1991.**)
thus