ON THE GENERATIVE CAPACITY OF COLONIES

We consider here colonies (grammar systems having as components regula r grammars generating finite languages) with various derivation modes (, t, less-than-or-equal-to k, = k, greater-than-or-equal-to k, as us ual in grammar systems area). Their generative capacity is investigate d. Problems still open in the theory of general grammar systems (conce rning, for instance, hierarchies on the number of components and on th e parameter k mentioned above) are solved for this particular case. Wh en hypothesis languages are added or the cooperation is aided by a tra nsducer, the family of context-sensitive languages is characterized in most of these derivation modes.