Nuprl Lemma : sq_stable__vdf-eq
∀[A,B:Type]. ∀[C:A ⟶ B ⟶ Type]. ∀[f:very-dep-fun(A;B;a,b.C[a;b])]. ∀[L:(a:A × b:B × C[a;b]) List].
  SqStable(vdf-eq(A;f;L))
Proof
Definitions occuring in Statement : 
very-dep-fun: very-dep-fun(A;B;a,b.C[a; b])
, 
vdf-eq: vdf-eq(A;f;L)
, 
list: T List
, 
sq_stable: SqStable(P)
, 
uall: ∀[x:A]. B[x]
, 
so_apply: x[s1;s2]
, 
function: x:A ⟶ B[x]
, 
product: x:A × B[x]
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
sq_stable: SqStable(P)
, 
implies: P 
⇒ Q
, 
squash: ↓T
, 
member: t ∈ T
, 
so_lambda: λ2x y.t[x; y]
, 
so_apply: x[s1;s2]
, 
uimplies: b supposing a
, 
all: ∀x:A. B[x]
, 
prop: ℙ
Lemmas referenced : 
vdf-eq-witness, 
squash_wf, 
vdf-eq_wf, 
list_wf, 
very-dep-fun_wf, 
istype-universe
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
lambdaFormation_alt, 
sqequalHypSubstitution, 
imageElimination, 
introduction, 
cut, 
extract_by_obid, 
isectElimination, 
thin, 
hypothesisEquality, 
sqequalRule, 
lambdaEquality_alt, 
applyEquality, 
universeIsType, 
independent_isectElimination, 
hypothesis, 
dependent_functionElimination, 
productEquality, 
functionIsType, 
inhabitedIsType, 
instantiate, 
universeEquality
Latex:
\mforall{}[A,B:Type].  \mforall{}[C:A  {}\mrightarrow{}  B  {}\mrightarrow{}  Type].  \mforall{}[f:very-dep-fun(A;B;a,b.C[a;b])].  \mforall{}[L:(a:A  \mtimes{}  b:B  \mtimes{}  C[a;b])  List].
    SqStable(vdf-eq(A;f;L))
Date html generated:
2020_05_19-PM-09_40_46
Last ObjectModification:
2020_03_06-PM-01_24_30
Theory : co-recursion-2
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