Language representations starting from fully initial languages
It is proved that each regular/linear/context-free language is the image of a fully initial regular/linear/context-free language by an inverse homomorphism, as well as the intersection of two regular/linear/context-free fully initial languages, respectively. The converse of the latter assertion is not true for linear and for context-free languages.
Gyenizse Pal 1996. Szeptember 4. Szerda 14:19:59 MET DST