d-Primitive Words and Contextual Grammars

Tetsuo MORIYA, Itaru KATAOKA
2012 IEICE transactions on information and systems  
In this paper we study the ploblem whether the language D(1) of all d-primitive words can be generated by a contextual grammar. It is proved that D(1) can be generated neither by an external contextual grammar nor by an internal contextual grammar, and that it can be generated by a total contextual grammar with choice.
doi:10.1587/transinf.e95.d.2710 fatcat:mb662pa76ncphbys4mbdngzf3a