All Questions
Tagged with decidability turing-recognizable
5 questions
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If a language L over a finite alphabet A has both a subset and superset that are Turing-recognizable, does this make L Turing-Recognizable too?
"Let A be a finite alphabet, and let L1 and L2 be two Turing-recognisable languages over A such that L1 is a proper subset of L2, i.e. L1 ⊂ L2 but L1 ≠ L2. Let a language L over the alphabet A ...
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Proving a language is recursively enumerable
Prove that the following language is recursively enumerable:
L = {<M,x> | Turing machine M enters the same configuration twice on input x}
I have tried to construct a TM that maintains the ...
- 90
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If a language is undecidable, then its complementary language must also be undecidable?
Reference from here If a Language is Non-Recognizable then what about its complement?
There exist complementary languages of unrecognizable languages that are recognizable, and there exist ...
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Unrecognizable languages must be undecidable?
A decidable language must be recognizable.
Unrecognizable languages must be undecidable?
I want to know more about the relation of undecidability and unrecognizability
- 317
1
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L is a recognizable undecidable language ,M is a Turing machine that recognizes L, does M reject or infinitely loop for s belonging to L-complement?
If $L$ is a decidable language, $M$ is a Turing machine that determines $L$. For $\forall s \in L$, M accepts, and for $\forall s \in \overline{L}$, M rejects
However, my question is that
If $L$ is a ...
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