4
Buchi’s Theorem
•
MSO
µ
regular languages
•
This is harder: let
f
2
MSO.
Need to show that
the set {M | M
˛
f
} is regular
•
•
Proof 1 (not in the book): induction on
f
[in class]
•
•
Proof 2 (from the book): using types [in class]