Context-freeness of the Languages of Schützenberger Automata of Hnn-extensions of Finite Inverse Semigroups
نویسندگان
چکیده
We prove that the Schützenberger graph of any element of the HNN-extension of a finite inverse semigroup S with respect to its standard presentation is a context-free graph in the sense of [11], showing that the language L recognized by this automaton is context-free. Finally we explicitly construct the grammar generating L, and from this fact we show that the word problem for an HNN-extension of a finite inverse semigroup S is decidable and lies in the complexity class of polynomial time problems.
منابع مشابه
Hnn - Extensions of F Inite I Nverse S Emigroups
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