Nuprl Lemma : decidable__l_exists-proof

∀[A:Type]. ∀[F:A ⟶ ℙ].  ∀L:A List. ((∀k:A. Dec(F[k])) ⇒ Dec((∃k∈L. F[k])))


Proof




Definitions occuring in Statement :  l_exists: (∃x∈L. P[x]),  list: T List,  decidable: Dec(P),  uall: ∀[x:A]. B[x],  prop: ℙ,  so_apply: x[s],  all: ∀x:A. B[x],  implies: P ⇒ Q,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  l_exists: (∃x∈L. P[x]),  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  so_lambda: λ2x.t[x],  so_apply: x[s],  int_seg: {i..j-},  uimplies: b supposing a,  guard: {T},  lelt: i ≤ j < k,  and: P ∧ Q,  decidable: Dec(P),  or: P ∨ Q,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  not: ¬A,  top: Top,  prop: ℙ,  less_than: a < b,  squash: ↓T
Lemmas referenced :  list_wf,  decidable_wf,  all_wf,  int_seg_wf,  int_formula_prop_less_lemma,  intformless_wf,  decidable__lt,  int_formula_prop_wf,  int_term_value_var_lemma,  int_term_value_constant_lemma,  int_formula_prop_le_lemma,  int_formula_prop_not_lemma,  int_formula_prop_and_lemma,  itermVar_wf,  itermConstant_wf,  intformle_wf,  intformnot_wf,  intformand_wf,  satisfiable-full-omega-tt,  decidable__le,  int_seg_properties,  select_wf,  length_wf,  decidable__exists_int_seg
Rules used in proof :  sqequalSubstitution,  sqequalRule,  sqequalReflexivity,  sqequalTransitivity,  computationStep,  isect_memberFormation,  lambdaFormation,  cut,  thin,  instantiate,  lemma_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  natural_numberEquality,  isectElimination,  hypothesisEquality,  hypothesis,  lambdaEquality,  applyEquality,  cumulativity,  setElimination,  rename,  independent_isectElimination,  because_Cache,  productElimination,  unionElimination,  dependent_pairFormation,  int_eqEquality,  intEquality,  isect_memberEquality,  voidElimination,  voidEquality,  independent_pairFormation,  computeAll,  imageElimination,  independent_functionElimination,  introduction,  functionEquality,  universeEquality

Latex:
\mforall{}[A:Type].  \mforall{}[F:A  {}\mrightarrow{}  \mBbbP{}].    \mforall{}L:A  List.  ((\mforall{}k:A.  Dec(F[k]))  {}\mRightarrow{}  Dec((\mexists{}k\mmember{}L.  F[k])))



Date html generated: 2016_05_14-AM-07_47_52
Last ObjectModification: 2016_01_15-AM-08_33_00

Theory : list_1


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