Alternative Automata Characterization of Piecewise Testable Languages
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چکیده
We present a transparent condition on a minimal automaton which is equivalent to piecewise testability of the corresponding regular language. The condition simplifies the original Simon’s condition on the minimal automaton in a different way than conditions of Stern and Trahtman. Secondly, we prove that every piecewise testable language L is k-piecewise testable for k equal to the depth of the minimal DFA of L. This result improves all previously known estimates of such k.
منابع مشابه
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تاریخ انتشار 2013