Automata on Infinite Objects and Their Applications to Logic and Programming

We introduce various types of w-automata, top-down automata and bottom-up automata on infinite trees. We study the power of deterministic and nondeter-ministic tree automata and prove that deterministic and non-deterministic bottom-up tree automata accept the same intinite tree sets. We establish a relationship between tree automata, Logic programs, recursive program schemes, and the monadic second-order theory of the tree. We prove that the equivalence of two rational logic programs is decidable. \r7 1989 Academic Press. Inc. CONTENTS Introduction.