Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
I have one small question about the pumping lemma for regular languages – is it good enough to show that if a specific string belonging to a language L can’t be pumped, then the language is irregular? For example – if I choose language L1 being of the form a^nb^n (ab, aabb, aaabbb …) and I show that the string aabb can’t be pumped and still be a part of L1, then is it valid for me to immediately conclude that L1 is irregular?
Cheers.
It’s not quite sufficient to demonstrate that a single, finite-length string does not pump. For a rigorous argument, you’d also have to prove that length of your example string is greater than the pumping length of the language. Usually you assume that some pumping length
p exists, then construct a string longer than p that cannot be pumped.