Nuprl Lemma : can-apply-mu'
∀[A:Type]. ∀P:A ⟶ ℕ ⟶ 𝔹. ∀d:∀x:A. Dec(∃n:ℕ. (↑(P x n))). ∀x:A.  (↑can-apply(mu'(P);x) 
⇐⇒ ∃n:ℕ. (↑(P x n)))
Proof
Definitions occuring in Statement : 
mu': mu'(P)
, 
can-apply: can-apply(f;x)
, 
nat: ℕ
, 
assert: ↑b
, 
bool: 𝔹
, 
decidable: Dec(P)
, 
uall: ∀[x:A]. B[x]
, 
all: ∀x:A. B[x]
, 
exists: ∃x:A. B[x]
, 
iff: P 
⇐⇒ Q
, 
apply: f a
, 
function: x:A ⟶ B[x]
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
all: ∀x:A. B[x]
, 
mu': mu'(P)
, 
can-apply: can-apply(f;x)
, 
p-mu-decider, 
member: t ∈ T
, 
prop: ℙ
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
subtype_rel: A ⊆r B
, 
implies: P 
⇒ Q
, 
exists: ∃x:A. B[x]
, 
pi1: fst(t)
, 
isl: isl(x)
, 
assert: ↑b
, 
ifthenelse: if b then t else f fi 
, 
btrue: tt
, 
p-mu: p-mu(P;x)
, 
and: P ∧ Q
, 
iff: P 
⇐⇒ Q
, 
rev_implies: P 
⇐ Q
, 
true: True
, 
bfalse: ff
, 
false: False
, 
uiff: uiff(P;Q)
, 
uimplies: b supposing a
, 
not: ¬A
Lemmas referenced : 
all_wf, 
decidable_wf, 
exists_wf, 
nat_wf, 
assert_wf, 
bool_wf, 
p-mu-decider, 
top_wf, 
p-mu_wf, 
true_wf, 
false_wf, 
not_over_exists, 
equal_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
lambdaFormation, 
sqequalRule, 
hypothesisEquality, 
cut, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
lambdaEquality, 
hypothesis, 
applyEquality, 
functionEquality, 
universeEquality, 
instantiate, 
equalityTransitivity, 
equalitySymmetry, 
isectEquality, 
cumulativity, 
unionEquality, 
functionExtensionality, 
because_Cache, 
productElimination, 
unionElimination, 
independent_pairFormation, 
dependent_pairFormation, 
natural_numberEquality, 
voidElimination, 
independent_isectElimination, 
independent_functionElimination, 
dependent_functionElimination
Latex:
\mforall{}[A:Type]
    \mforall{}P:A  {}\mrightarrow{}  \mBbbN{}  {}\mrightarrow{}  \mBbbB{}.  \mforall{}d:\mforall{}x:A.  Dec(\mexists{}n:\mBbbN{}.  (\muparrow{}(P  x  n))).  \mforall{}x:A.    (\muparrow{}can-apply(mu'(P);x)  \mLeftarrow{}{}\mRightarrow{}  \mexists{}n:\mBbbN{}.  (\muparrow{}(P  x  n)))
Date html generated:
2018_05_21-PM-06_29_49
Last ObjectModification:
2018_05_19-PM-04_40_29
Theory : general
Home
Index