Major Section: ACL2-BUILT-INS
The natural numbers is the set of all non-negative integers,
{0,1,2,3,...}. Natp returns t if and only its argument is a
natural number, and nil otherwise. We recommend the community book
books/arithmetic/natp-posp.lisp as a book for reasoning about posp
and natp. This book is included by community books
books/arithmetic/top and books/arithmetic/top-with-meta.
To see the ACL2 definition of this function, see pf.
