Algebraic Systems

The last chapter of this book discusses algebraic power series and their relation to context-free grammars and languages. The notion Aalg«∑*» was already defined above in connection with pushdown automata in Section 10. We now consider the series in this collection from a new angle, corresponding to defining equations. The defining equations are algebraic in the classical sense, i.e., polynomial equations. However, their rather specific form reflects the particular requirements for context-free grammars.