Piecewise testable languages via combinatorics on words
نویسنده
چکیده
A regular language L over an alphabet A is called piecewise testable if it is a finite boolean combination of languages of the form Aa1A a2A ∗ . . . Aa`A ∗, where a1, . . . , a` ∈ A, ` ≥ 0. An effective characterization of piecewise testable languages was given in 1972 by Simon who proved that a language L is piecewise testable if and only if its syntactic monoid is J -trivial. Nowadays there exist several proofs of this result based on various methods from algebraic theory of regular languages. Our contribution adds a new purely combinatorial proof.
منابع مشابه
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 311 شماره
صفحات -
تاریخ انتشار 2011