Constrains, Stable, Invariant...more of the substitution axiom, but Union
does not work well with them
(* Title: HOL/UNITY/LessThan
ID: $Id$
Author: Lawrence C Paulson, Cambridge University Computer Laboratory
Copyright 1998 University of Cambridge
lessThan, greaterThan, atLeast, atMost
*)
LessThan = Main +
constdefs
lessThan :: "nat => nat set"
"lessThan n == {i. i<n}"
atMost :: "nat => nat set"
"atMost n == {i. i<=n}"
greaterThan :: "nat => nat set"
"greaterThan n == {i. n<i}"
atLeast :: "nat => nat set"
"atLeast n == {i. n<=i}"
end