In Class exercise on pumping lemma	Feb 12, 2008	


2 states, sigma={a, b}, check emptiness.

Draw a dfa for accepting {epsilon, ab, aabb}. 
Extend it for a constant M: {a^n b^n | 0<=n<=M}.

4.1.1e, p131

4.1.2a

4.1.2h

Prove infinte lang has a string of length between n and 2n, for n state dfa.
Describe alg to check infinteness.

3) 2 states, sigma={a, b}, check infinteness of languages.