(ii) there exists a Myhill-Nerode relation for R.
(iii) the relation ≡ R is of finite index.
38. What is an acceptor?
Automaton whose output response is ‘Yes’ or ‘No’ is called an
acceptor.
39. What is a regular expression?
It is a mathematical tool built from a set of primitive and operations.
40. What are the properties of regular sets?
(a) Clo sure
(b) Union
(c) Concatenation
(d) Negation
(e) Kleene star
(f) Intersection
(g) Set difference
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Theory of Automata, Formal Languages and Computation