n:, T:Type, R:(TTprop{i:l}), x,y:T.
(x rel_exp(T; R; n) y)
 ((z:T. ((0 < n) c ((x rel_exp(T; R; (n - 1)) z)  (z R y))))  ((n = 0  )  (x = y))) 

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Definitions	x:A. B(x), t  T, P  Q, P  Q, ge(i; j), A  B, A, False, prop{i:l}, P  Q, x f y, rel_exp(T; R; n), x:A. B(x), A c B, P  Q, P  Q, guard(T), Y, if b then t else f fi , (i = j), tt, , ff, sq_type(T), , Unit, decidable(P),
Lemmas	nat wf, nat properties, ge wf, rel exp wf, le wf, eq int wf, bool wf, iff transitivity, assert wf, eqtt to assert, assert of eq int, bnot wf, not wf, eqff to assert, assert of bnot, not functionality wrt iff, decidable int equal, bool cases, bool sq