On a conjecture of Schnoebelen
Antonio Cano Gómez, Jean-Éric Pin · 2008
The notion of sequential and parallel decomposition of a language over a set of languages was introduced by Schnoebelen. A language is decomposable if it belongs to a finite set of languages S such that each member of S admits a sequential and parallel decomposition over S. We disprove a conjecture of Schnoebelen concerning decomposable languages and establish some new properties of these languages. 1