EVENP

test whether an integer is even 
Major Section:  PROGRAMMING

(evenp x) is true if and only if the integer x is even. Actually, in the ACL2 logic (evenp x) is defined to be true when x/2 is an integer.

The guard for evenp requires its argument to be an integer.

Evenp is a Common Lisp function. See any Common Lisp documentation for more information.