Equational properties of stratified least fixed points

Abstract

Recently, a novel fixed point operation has been introduced over certain non-monotonic functions between stratified complete lattices and used to give semantics to logic programs with negation and boolean context-free grammars. We prove that this new operation satisfies `the standard' identities of fixed point operations as described by the axioms of iteration theories. We also study this new fixed point operation in connection with lambda-abstraction.