13
EVEN
•
Theorem
EVEN is not expressible in L
w
1
,
w
•
•
Corollary
•
EVEN is not expressible in LFP, IFP, PFP
•
•
Corollary
–
LFP
&
(LFP+<)
inv
–
IFP
&
(IFP+<)
inv
–
PFP
&
(PFP+<)
inv