Nuprl Lemma : simple-decidable-finite-cantor-ext
∀[T:Type]. ∀[R:T ⟶ ℙ].  ((∀x:T. Dec(R[x])) ⇒ (∀n:ℕ. ∀F:(ℕn ⟶ 𝔹) ⟶ T.  Dec(∃f:ℕn ⟶ 𝔹. R[F f])))
Proof
Definitions occuring in Statement : 
int_seg: {i..j-}, 
nat: ℕ, 
bool: 𝔹, 
decidable: Dec(P), 
uall: ∀[x:A]. B[x], 
prop: ℙ, 
so_apply: x[s], 
all: ∀x:A. B[x], 
exists: ∃x:A. B[x], 
implies: P ⇒ Q, 
apply: f a, 
function: x:A ⟶ B[x], 
natural_number: $n, 
universe: Type
Definitions unfolded in proof : 
member: t ∈ T, 
it: ⋅, 
ifthenelse: if b then t else f fi , 
simple-finite-cantor-decider: FiniteCantorDecide(dcdr;n;F), 
simple-decidable-finite-cantor, 
sq_stable_from_decidable, 
sq_stable__from_stable, 
stable__from_decidable, 
any: any x
Lemmas referenced : 
simple-decidable-finite-cantor, 
sq_stable_from_decidable, 
sq_stable__from_stable, 
stable__from_decidable
Rules used in proof : 
introduction, 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
cut, 
instantiate, 
extract_by_obid, 
hypothesis, 
sqequalRule, 
thin, 
sqequalHypSubstitution, 
equalityTransitivity, 
equalitySymmetry
Latex:
\mforall{}[T:Type].  \mforall{}[R:T  {}\mrightarrow{}  \mBbbP{}].    ((\mforall{}x:T.  Dec(R[x]))  {}\mRightarrow{}  (\mforall{}n:\mBbbN{}.  \mforall{}F:(\mBbbN{}n  {}\mrightarrow{}  \mBbbB{})  {}\mrightarrow{}  T.    Dec(\mexists{}f:\mBbbN{}n  {}\mrightarrow{}  \mBbbB{}.  R[F  f])))
Date html generated:
2018_05_21-PM-01_17_25
Last ObjectModification:
2018_05_19-AM-06_32_32
Theory : continuity
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