NOTE This topic/question is purely mathematical, but potentially with some interesting relevance to multi-agent systems in the AI sense.
Suppose, for example, I want a network that once started will run indefinitely, always visiting all of its states before repetition. What is (1) a sufficient condition and (2) a necessary condition for this property?
NOTE For the precise definition of a Finite State Automaton (aka Finite State Machine) see any relevant textbook or the Wikipedia article.