Nuprl Lemma : fan-theorem

∀[X:(𝔹 List) ⟶ ℙ]. (tbar(𝔹;X) ⇒ Decidable(X) ⇒ (∃k:ℕ. ∀f:ℕ ⟶ 𝔹. ∃n:ℕk. (X map(f;upto(n)))))


Proof




Definitions occuring in Statement :  tbar: tbar(T;X),  dec-predicate: Decidable(X),  upto: upto(n),  map: map(f;as),  list: T List,  int_seg: {i..j-},  nat: ℕ,  bool: 𝔹,  uall: ∀[x:A]. B[x],  prop: ℙ,  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  implies: P ⇒ Q,  apply: f a,  function: x:A ⟶ B[x],  natural_number: $n
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  member: t ∈ T,  prop: ℙ,  all: ∀x:A. B[x],  sq_exists: ∃x:{A| B[x]},  exists: ∃x:A. B[x],  so_lambda: λ2x.t[x],  nat: ℕ,  int_seg: {i..j-},  subtype_rel: A ⊆r B,  so_apply: x[s],  uimplies: b supposing a,  le: A ≤ B,  and: P ∧ Q,  less_than': less_than'(a;b),  false: False,  not: ¬A,  uiff: uiff(P;Q),  dec-predicate: Decidable(X),  decidable: Dec(P),  or: P ∨ Q,  outl: outl(x)
Lemmas referenced :  dec-predicate_wf,  list_wf,  bool_wf,  tbar_wf,  simple-fan-theorem,  nat_wf,  all_wf,  exists_wf,  int_seg_wf,  map_wf,  subtype_rel_dep_function,  int_seg_subtype_nat,  false_wf,  subtype_rel_self,  upto_wf,  not_over_exists,  not_wf,  int_seg_decide_wf,  decidable_wf,  equal_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  rename,  cut,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesis,  hypothesisEquality,  functionEquality,  cumulativity,  universeEquality,  dependent_functionElimination,  setElimination,  dependent_pairFormation,  sqequalRule,  lambdaEquality,  natural_numberEquality,  applyEquality,  because_Cache,  independent_isectElimination,  independent_pairFormation,  addLevel,  impliesFunctionality,  productElimination,  independent_functionElimination,  voidElimination,  introduction,  instantiate,  equalityTransitivity,  equalitySymmetry,  unionElimination

Latex:
\mforall{}[X:(\mBbbB{}  List)  {}\mrightarrow{}  \mBbbP{}].  (tbar(\mBbbB{};X)  {}\mRightarrow{}  Decidable(X)  {}\mRightarrow{}  (\mexists{}k:\mBbbN{}.  \mforall{}f:\mBbbN{}  {}\mrightarrow{}  \mBbbB{}.  \mexists{}n:\mBbbN{}k.  (X  map(f;upto(n)))))



Date html generated: 2016_05_15-PM-10_05_18
Last ObjectModification: 2015_12_27-PM-05_51_09

Theory : bar!induction


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