Nuprl Lemma : Escardo-Xu
¬(∀F:(ℕ ⟶ ℕ) ⟶ ℕ. ∃k:ℕ. ∀g:ℕ ⟶ ℕ. ((∀i:ℕk. ((g i) = 0 ∈ ℕ)) ⇒ ((F (λi.0)) = (F g) ∈ ℕ)))
Proof
Definitions occuring in Statement : 
int_seg: {i..j-}, 
nat: ℕ, 
all: ∀x:A. B[x], 
exists: ∃x:A. B[x], 
not: ¬A, 
implies: P ⇒ Q, 
apply: f a, 
lambda: λx.A[x], 
function: x:A ⟶ B[x], 
natural_number: $n, 
equal: s = t ∈ T
Definitions unfolded in proof : 
lelt: i ≤ j < k, 
int_seg: {i..j-}, 
rev_implies: P ⇐ Q, 
iff: P ⇐⇒ Q, 
true: True, 
top: Top, 
satisfiable_int_formula: satisfiable_int_formula(fmla), 
decidable: Dec(P), 
ge: i ≥ j , 
squash: ↓T, 
assert: ↑b, 
bnot: ¬bb, 
guard: {T}, 
sq_type: SQType(T), 
or: P ∨ Q, 
bfalse: ff, 
uimplies: b supposing a, 
uiff: uiff(P;Q), 
ifthenelse: if b then t else f fi , 
btrue: tt, 
it: ⋅, 
unit: Unit, 
bool: 𝔹, 
pi1: fst(t), 
subtype_rel: A ⊆r B, 
exists: ∃x:A. B[x], 
false: False, 
less_than': less_than'(a;b), 
and: P ∧ Q, 
le: A ≤ B, 
all: ∀x:A. B[x], 
so_apply: x[s], 
nat: ℕ, 
so_lambda: λ2x.t[x], 
uall: ∀[x:A]. B[x], 
prop: ℙ, 
member: t ∈ T, 
implies: P ⇒ Q, 
not: ¬A
Lemmas referenced : 
decidable__le, 
int_formula_prop_le_lemma, 
intformle_wf, 
ifthenelse_wf, 
assert_of_bnot, 
iff_weakening_uiff, 
iff_transitivity, 
bool_cases, 
not_wf, 
bnot_wf, 
assert_wf, 
int_seg_subtype_nat, 
decidable__lt, 
int_term_value_var_lemma, 
int_formula_prop_less_lemma, 
int_formula_prop_and_lemma, 
itermVar_wf, 
intformless_wf, 
intformand_wf, 
int_seg_properties, 
iff_weakening_equal, 
int_formula_prop_wf, 
int_term_value_constant_lemma, 
int_formula_prop_eq_lemma, 
int_formula_prop_not_lemma, 
itermConstant_wf, 
intformeq_wf, 
intformnot_wf, 
full-omega-unsat, 
decidable__equal_int, 
nat_properties, 
true_wf, 
squash_wf, 
int_subtype_base, 
set_subtype_base, 
less_than_wf, 
assert-bnot, 
bool_subtype_base, 
subtype_base_sq, 
bool_cases_sqequal, 
eqff_to_assert, 
assert_of_lt_int, 
eqtt_to_assert, 
bool_wf, 
lt_int_wf, 
le_wf, 
false_wf, 
equal_wf, 
equal-wf-T-base, 
int_seg_wf, 
exists_wf, 
nat_wf, 
all_wf
Rules used in proof : 
impliesFunctionality, 
int_eqEquality, 
baseClosed, 
imageMemberEquality, 
voidEquality, 
isect_memberEquality, 
approximateComputation, 
applyLambdaEquality, 
levelHypothesis, 
equalityUniverse, 
universeEquality, 
imageElimination, 
intEquality, 
voidElimination, 
cumulativity, 
instantiate, 
independent_isectElimination, 
equalityElimination, 
unionElimination, 
independent_functionElimination, 
dependent_functionElimination, 
equalitySymmetry, 
equalityTransitivity, 
dependent_pairFormation, 
productElimination, 
promote_hyp, 
independent_pairFormation, 
dependent_set_memberEquality, 
hypothesisEquality, 
functionExtensionality, 
applyEquality, 
rename, 
setElimination, 
natural_numberEquality, 
because_Cache, 
lambdaEquality, 
sqequalRule, 
hypothesis, 
functionEquality, 
thin, 
isectElimination, 
sqequalHypSubstitution, 
extract_by_obid, 
introduction, 
cut, 
lambdaFormation, 
sqequalReflexivity, 
computationStep, 
sqequalTransitivity, 
sqequalSubstitution
Latex:
\mneg{}(\mforall{}F:(\mBbbN{}  {}\mrightarrow{}  \mBbbN{})  {}\mrightarrow{}  \mBbbN{}.  \mexists{}k:\mBbbN{}.  \mforall{}g:\mBbbN{}  {}\mrightarrow{}  \mBbbN{}.  ((\mforall{}i:\mBbbN{}k.  ((g  i)  =  0))  {}\mRightarrow{}  ((F  (\mlambda{}i.0))  =  (F  g))))
Date html generated:
2017_09_29-PM-06_05_02
Last ObjectModification:
2017_09_22-PM-04_45_41
Theory : fan-theorem
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