Nuprl Lemma : simple_fan_theorem'

∀[X:n:ℕ ⟶ (ℕn ⟶ 𝔹) ⟶ ℙ]
  (∀n:ℕ. ∀s:ℕn ⟶ 𝔹.  Dec(X[n;s])) ⇒ (∃k:ℕ [(∀f:ℕ ⟶ 𝔹. ∃n:ℕk. X[n;f])]) supposing ∀f:ℕ ⟶ 𝔹. (↓∃n:ℕ. X[n;f])


Proof




Definitions occuring in Statement :  int_seg: {i..j-},  nat: ℕ,  bool: 𝔹,  decidable: Dec(P),  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  prop: ℙ,  so_apply: x[s1;s2],  all: ∀x:A. B[x],  sq_exists: ∃x:A [B[x]],  exists: ∃x:A. B[x],  squash: ↓T,  implies: P ⇒ Q,  function: x:A ⟶ B[x],  natural_number: $n
Definitions unfolded in proof :  true: True,  top: Top,  subtract: n - m,  uiff: uiff(P;Q),  rev_implies: P ⇐ Q,  iff: P ⇐⇒ Q,  or: P ∨ Q,  decidable: Dec(P),  so_apply: x[s],  not: ¬A,  false: False,  less_than': less_than'(a;b),  le: A ≤ B,  subtype_rel: A ⊆r B,  prop: ℙ,  and: P ∧ Q,  lelt: i ≤ j < k,  sq_stable: SqStable(P),  guard: {T},  int_seg: {i..j-},  so_apply: x[s1;s2],  nat: ℕ,  so_lambda: λ2x.t[x],  so_lambda: λ2x y.t[x; y],  implies: P ⇒ Q,  squash: ↓T,  all: ∀x:A. B[x],  member: t ∈ T,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  less_than: a < b,  exists: ∃x:A. B[x],  sq_exists: ∃x:A [B[x]],  assert: ↑b,  ifthenelse: if b then t else f fi ,  bnot: ¬bb,  sq_type: SQType(T),  bfalse: ff,  btrue: tt,  it: ⋅,  unit: Unit,  bool: 𝔹,  seq-append: seq-append(n;m;s1;s2),  cand: A c∧ B,  seq-adjoin: s++t,  ge: i ≥ j ,  nat_plus: ℕ+
Lemmas referenced :  squash_wf,  decidable_wf,  seq-adjoin_wf,  le-add-cancel,  add-zero,  add_functionality_wrt_le,  add-commutes,  add-swap,  add-associates,  minus-one-mul-top,  zero-add,  minus-one-mul,  minus-add,  condition-implies-le,  not-le-2,  decidable__le,  subtype_rel_self,  subtype_rel_function,  false_wf,  int_seg_subtype_nat,  seq-append_wf,  le_wf,  equal_wf,  sq_stable__le,  add_nat_wf,  int_seg_wf,  exists_wf,  all_wf,  sq_exists_wf,  basic_bar_induction,  bool_wf,  nat_wf,  less_than_wf,  and_wf,  less-iff-le,  not-lt-2,  assert-bnot,  bool_subtype_base,  subtype_base_sq,  bool_cases_sqequal,  eqff_to_assert,  top_wf,  assert_of_lt_int,  eqtt_to_assert,  lt_int_wf,  btrue_wf,  bfalse_wf,  imax_wf,  imax_nat,  istype-false,  istype-le,  istype-void,  add-member-int_seg2,  subtract_wf,  le-add-cancel2,  istype-less_than,  ifthenelse_wf,  le_int_wf,  assert_of_le_int,  decidable__lt,  minus-minus,  iff_weakening_uiff,  assert_wf,  true_wf,  istype-int,  add_functionality_wrt_eq,  imax_unfold,  iff_weakening_equal,  istype-top,  le_weakening2,  add-is-int-iff,  set_subtype_base,  int_subtype_base,  le_reflexive,  minus-zero,  one-mul,  add-mul-special,  zero-mul,  two-mul,  mul-distributes-right,  omega-shadow,  mul-distributes,  mul-associates,  mul-commutes,  le-add-cancel-alt,  nat_properties,  iff_imp_equal_bool,  not-less-implies-equal,  sq_stable__and,  sq_stable__less_than,  member-less_than,  decidable__int_equal,  not-equal-2,  less_than_irreflexivity,  less_than_transitivity1
Rules used in proof :  universeEquality,  cumulativity,  minusEquality,  intEquality,  voidEquality,  isect_memberEquality,  voidElimination,  unionElimination,  independent_pairFormation,  independent_isectElimination,  equalitySymmetry,  equalityTransitivity,  productElimination,  independent_functionElimination,  addEquality,  dependent_set_memberEquality,  functionExtensionality,  applyEquality,  setElimination,  natural_numberEquality,  because_Cache,  isectElimination,  lambdaFormation,  rename,  extract_by_obid,  functionEquality,  baseClosed,  imageMemberEquality,  hypothesis,  imageElimination,  hypothesisEquality,  thin,  dependent_functionElimination,  lambdaEquality,  sqequalHypSubstitution,  sqequalRule,  introduction,  cut,  isect_memberFormation,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution,  dependent_pairFormation,  dependent_set_memberFormation,  levelHypothesis,  hyp_replacement,  addLevel,  instantiate,  promote_hyp,  axiomSqEquality,  lessCases,  equalityElimination,  Error :dependent_set_memberFormation_alt,  Error :dependent_set_memberEquality_alt,  Error :lambdaFormation_alt,  Error :inhabitedIsType,  Error :equalityIstype,  Error :functionIsType,  Error :universeIsType,  Error :productIsType,  Error :lambdaEquality_alt,  Error :isect_memberEquality_alt,  Error :dependent_pairFormation_alt,  closedConclusion,  Error :functionExtensionality_alt,  Error :isect_memberFormation_alt,  Error :isectIsTypeImplies,  multiplyEquality,  baseApply,  Error :functionIsTypeImplies

Latex:
\mforall{}[X:n:\mBbbN{}  {}\mrightarrow{}  (\mBbbN{}n  {}\mrightarrow{}  \mBbbB{})  {}\mrightarrow{}  \mBbbP{}]
    (\mforall{}n:\mBbbN{}.  \mforall{}s:\mBbbN{}n  {}\mrightarrow{}  \mBbbB{}.    Dec(X[n;s]))  {}\mRightarrow{}  (\mexists{}k:\mBbbN{}  [(\mforall{}f:\mBbbN{}  {}\mrightarrow{}  \mBbbB{}.  \mexists{}n:\mBbbN{}k.  X[n;f])]) 
    supposing  \mforall{}f:\mBbbN{}  {}\mrightarrow{}  \mBbbB{}.  (\mdownarrow{}\mexists{}n:\mBbbN{}.  X[n;f])



Date html generated: 2019_06_20-AM-11_32_53
Last ObjectModification: 2019_01_27-PM-01_30_43

Theory : bool_1


Home Index