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Discussion 2
•
Simultaneous fixpoints
•
•
Is there a path of even length from a to b ?
[
lfp
R,x
f
(R, S, x),
y
(R, S, x)](b)
Where
f
(R,S,x) =
9
z.(S(x,z)
Æ
E(z,x))
y
(R,S,x) = E(a,x)
Ç
9
z.(R(x,z)
Æ
E(z,x))
EXPRESS THE SAME THING WITH ONLY ONE LFP !