Chomsky-schutzenberger, Theory of Computation

The upper string r ∈ Q+ is the sequence of states visited by the automaton as it scans the lower string w ∈ Σ*. We will refer to this string over Q as the run of A on w. The automaton A accepts w iff the run of A on w ends in an accepting state. (If A is non-deterministic there will potentially be many runs with the automaton accepting if any one of them ends in an accepting state.) Note that the set of runs of an automaton is an SL2 language, recognized by the SL2 automaton (over Q) one gets by projecting away the third component of the triples of GA. Thus there is some kind of close relationship between the strictly local languages and the recognizable languages.

To get at this we will start by working in the other direction, extending our tiles to hold four symbols. The idea is to include, for each tile (q, p, σ) ∈ GA, a tile extended with σ′ for each σ′ ∈ Σ. (We don't actually need tiles for all such σ′ , only for those that occur on tiles (x, q, σ′) which might precede this one in a tiling, but including all of them will be harmless-the ones that do not occur on such tiles will just be useless.)

Posted Date: 3/21/2013 3:39:22 AM | Location : United States







Related Discussions:- Chomsky-schutzenberger, Assignment Help, Ask Question on Chomsky-schutzenberger, Get Answer, Expert's Help, Chomsky-schutzenberger Discussions

Write discussion on Chomsky-schutzenberger
Your posts are moderated
Related Questions
So we have that every language that can be constructed from SL languages using Boolean operations and concatenation (that is, every language in LTO) is recognizable but there are r

If the first three words are the boys down,what are the last three words??

Ask question #Minimum 100 words accepte

Theorem (Myhill-Nerode) A language L ⊆ Σ is recognizable iff ≡L partitions Σ* into ?nitely many Nerode equivalence classes. Proof: For the "only if" direction (that every recogn

Describe the architecture of interface agency

This close relationship between the SL2 languages and the recognizable languages lets us use some of what we know about SL 2 to discover properties of the recognizable languages.

Ask question #Minimum 100 words accepte

One might assume that non-closure under concatenation would imply non closure under both Kleene- and positive closure, since the concatenation of a language with itself is included

shell script to print table in given range

Find the Regular Grammar for the following Regular Expression: a(a+b)*(ab*+ba*)b.