test whether an integer is even
Major Section:  ACL2-BUILT-INS

(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.

To see the ACL2 definition of this function, see pf.