; The Collatz conjecture as a mathematical feedback equation:
out = (in/2) - (((5*in) + 2)*(((-1)^in) - 1)/4)
; Prove that feeding "out" into "in" will
; always eventually count down to the number 1.
; Run with the command "calc in".
; Repeatedly prompt with the command "repeat calc in".
; See all intermediate in/out values by typing "set debug 1" beforehand.