A Complete Density Range of Continuum-Many Non-Context-Free Languages Fulfilling Strong Iteration Properties
Horváth, Sándor, Manfred Kudlek · Universitätsbibliothek Gießen · 2010
We show that the cardinality of languages fulfilling all strong iteration lemmata for context-free languages, and having either an exponential, polynomial, or superpolynomial but sub-exponential density, is the cardinality of the continuum. In the last case we could prove this only for non-erasing iteration so far.