Lecture 3

Theorem (Pumping Lemma)
If A is a regular language, then there is a
number p (called the pumping length) such that
whenever s is a string in A of length ≥ p, then s
may be written s=xyz satisfying:
for each i ≥ 0, xy i z ∊ A,
|y| > 0, and
|xy| ≤ p
Friday, February 8, 13