Recognizing renamable generalized propositional Horn formulas is NP-complete
نویسندگان
چکیده
منابع مشابه
Recognizing Renamable Generalized Propositional Horn Formulas Is NP-complete
Yamasaki and Doshita have defined an extension of the class of propositional Horn formulas; later, Gallo and Scutellà generalized this class to a hierarchy Γ0 ⊆ Γ1 ⊆ . . . ⊆ Γk ⊆ . . ., where Γ0 is the set of Horn formulas and Γ1 is the class of Yamasaki and Doshita. For any fixed k, the propositional formulas in Γk can be recognized in polynomial time, and the satisfiability problem for Γk for...
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 1995
ISSN: 0166-218X
DOI: 10.1016/0166-218x(93)e0152-o