(applicable only to neighbourhood k<=5)
If ``d'' is selected in #13.6, the rule can be specified by its decimal equivalent. The following prompt is displayed.
n=3 rule, enter 0-255 (default random):
If just ``return'' is entered, or a number outside the permitted range, the selection will revert to ``random`` as in #13.10 below. When selected, the rule is also shown in hex and as the rule table bit pattern, and displayed the rule window.