•A = (S, Q, q0, d, F) where:
q0 2 Q, F µ Q
d is a set of tuples of the form:
• (w, a, q) w 2 Q*, a 2 S, q 2 Q, s.t. |w| = r(a)
•
•Execution: given a tree T, A
executes
bottom up or top
down [show in class]
•A language L µ Tree[S] is a regular tree language iff there exists A s.t. L = {T | T accepted by A}