When does a string belong to the set A of bit strings
Chapter 4, Problem 4.3.39(choose chapter or problem)
When does a string belong to the set A of bit strings defined recursively by AEA Ox 1 E A if x E A, where A is the empty string?
Unfortunately, we don't have that question answered yet. But you can get it answered in just 5 hours by Logging in or Becoming a subscriber.
Becoming a subscriber
Or look for another answer