CODING NESTED MIXING ONE-SIDED SUBSHIFTS OF FINITE-TYPE AS MARKOV SHIFTS HAVING EXACTLY THE SAME ALPHABET

Let X-0, X be mixing one-sided subshifts of finite type such that We s how a necessary and sufficient condition for the existence of mixing M arkov shifts Y-0, Y, Y-0 subset of or equal to Y, and a conjugacy pi : Y --> X with pi(Y-0) = X-0, such that the sets of letters appearing i n both systems are the same, more precisely, L-1(Y-0) = L-1(Y).