A Characterization of ET0L and EDT0L Languages
نویسنده
چکیده
There exists a PT0L language L0 such that the following holds. A language L is an ET0L language if and only if there exists a mapping T induced by an a-NGSM (nondeterministic generalized sequential machine with accepting states) such that L = T (L0). There exists an infinite collection of EPDT0L languages Dmn ⊆ Σ ⋆ mn (n ≥ m ≥ 1) such that the family EDT0L is characterized in the following way. A language L is an EDT0L language if and only if there exist n ≥ m ≥ 1, a homomorphism h and a regular language R ⊆ Σmn such that L = h(Dmn ∩ R).
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تاریخ انتشار 2010