The Correspondence Between The Horn Logic Programs And Grammars

In this paper , Horn logic programs with grammatical view is considered. Because the computability of Horn logic programs is equivalent to that of Turing machines and the latter are equivalent to that of type-0 grammars ,Horn logic programs are equivalent to type-0 grammars .This paper is to aim at exploring how Horn logic programs are equivalent to type-0 grammars and what is the characterics of Horn logic programs that are semantically equivalent to subclasses of type-0 grammars .In this paper, the results of research are as follows :The method to find type-0 grammars generating the least Herbrand models of Horn logic program is given .The method to find Horn logic programs generating the languages of type-0 grammars is given .The characterics of Horn logic programs that are semantically equivalent to recursive grammars,type-1 grammars,type-2 grammars, and type-3 grammars are given.