Step of Proof: decidable__iff 9,38
Inference at * 
Iof proof for Lemma decidable iff:


  P,Q:. Dec(P)  Dec(Q)  Dec(P  Q) 
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 by ((Repeat (Unfolds ``iff rev_implies`` 0)) 
CollapseTHEN ((Auto_aux (first_nat 1:n
C) ((first_nat 1:n),(first_nat 3:n)) (first_tok :t) inil_term))) 
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C.

Definitionst  T, P  Q, P  Q, P  Q, , x:A. B(x)
Lemmasdecidable wf, decidable implies, decidable and

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