Here, we have his construction in the modern notation used in automata theory.
His research career, which spans over forty years, is focused on formal languages and automata theory.
His work in automata theory led the switching theory community into a more theoretical direction.
Many hard problems in automata theory involve finding the right construction of an automaton such that the problem can be answered.
We recall a few concepts from graph theory and automata theory.
The input alphabet remains finite, and other typical concerns of automata theory remain in play.
In particular, he has written books on automata theory and the semantics of parallel computing.
Eilenberg also wrote an important book on automata theory.
In automata theory, a transition that involves no shifting of an input symbol.
Each model in automata theory plays important roles in several applied areas.