On the Commutative Equivalence of Bounded Semi-linear Codes

On the Commutative Equivalence of Algebraic Formal Series and Languages

“…Incidentally, it is maybe of interest to note that the authors investigated recently the Kleene closure of bounded semi-linear languages in connection with the CE Problem. In [11,13] the commutative regularity of these languages has been established, in the case that the bounded semi-linear language is a code satisfying some restriction on the number of letters of its words.…”

Coding by minimal linear grammars

“…It is worth noticing that UMLG seem to play an interesting role also in the study of the commutative equivalence of context-free and regular languages. Conditions ensuring that a language is commutatively equivalent with a regular one, have been obtained for the classes of bounded semi-linear languages and codes, context-free languages of finite index and UMLG [9,10,11,14,15,16].…”