Axiomatizing omega and omega-op powers of words
Stephen L. Bloom, Zoltán Ésik · RAIRO - Theoretical Informatics and Applications · 2004
In 1978, Courcelle asked for a complete set of axioms and rules for the equational theory of (discrete regular) words equipped with the operations of product, omega power and omega-op power. In this paper we find a simple set of equations and prove they are complete. Moreover, we show that the equational theory is decidable in polynomial time.