a1 Department of Mathematics, University of Maryland, College Park, MD 20742, USA
a2 Department of Mathematics, University of Washington, Seattle, WA 98195, USA
Two Markov chains are regularly isomorphic if and only if they have a common Markov extension by right closing block codes of degree one. A certain ideal class in the integral group ring of the ratio group associated to a Markov chain is a new invariant of regular isomorphism and some other coding relations.
(Received May 26 1988)
(Revised February 23 1989)
† M. Boyle was partially supported by NSF Grant DMS-8601619.