Nuprl Lemma : last_with_property

∀[T:Type]
  ∀L:T List
    ∀[P:ℕ||L|| ⟶ ℙ]
      ((∀x:ℕ||L||. Dec(P x)) ⇒ (∃i:ℕ||L||. (P i)) ⇒ (∃i:ℕ||L||. ((P i) ∧ (∀j:ℕ||L||. ¬(P j) supposing i < j))))


Proof




Definitions occuring in Statement :  length: ||as||,  list: T List,  int_seg: {i..j-},  less_than: a < b,  decidable: Dec(P),  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  prop: ℙ,  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  not: ¬A,  implies: P ⇒ Q,  and: P ∧ Q,  apply: f a,  function: x:A ⟶ B[x],  natural_number: $n,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  exists: ∃x:A. B[x],  and: P ∧ Q,  prop: ℙ,  so_lambda: λ2x.t[x],  so_apply: x[s],  guard: {T},  int_seg: {i..j-},  lelt: i ≤ j < k,  decidable: Dec(P),  or: P ∨ Q,  less_than: a < b,  squash: ↓T,  uimplies: b supposing a,  not: ¬A,  satisfiable_int_formula: satisfiable_int_formula(fmla),  false: False,  top: Top,  cand: A c∧ B,  subtype_rel: A ⊆r B,  interleaving_occurence: interleaving_occurence(T;L1;L2;L;f1;f2),  nat: ℕ,  ge: i ≥ j ,  sq_type: SQType(T)
Lemmas referenced :  interleaving_split,  exists_wf,  int_seg_wf,  length_wf,  all_wf,  decidable_wf,  list_wf,  int_seg_properties,  decidable__lt,  full-omega-unsat,  intformand_wf,  intformnot_wf,  intformless_wf,  itermConstant_wf,  itermVar_wf,  intformle_wf,  int_formula_prop_and_lemma,  int_formula_prop_not_lemma,  int_formula_prop_less_lemma,  int_term_value_constant_lemma,  int_term_value_var_lemma,  int_formula_prop_le_lemma,  int_formula_prop_wf,  subtract_wf,  decidable__le,  itermSubtract_wf,  int_term_value_subtract_lemma,  lelt_wf,  subtype_rel_self,  less_than_wf,  isect_wf,  not_wf,  increasing_implies,  length_wf_nat,  nat_properties,  intformeq_wf,  int_formula_prop_eq_lemma,  subtype_base_sq,  int_subtype_base,  decidable__equal_int
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  dependent_functionElimination,  independent_functionElimination,  hypothesis,  productElimination,  natural_numberEquality,  sqequalRule,  lambdaEquality,  applyEquality,  functionEquality,  cumulativity,  universeEquality,  setElimination,  rename,  unionElimination,  imageElimination,  independent_isectElimination,  approximateComputation,  dependent_pairFormation,  int_eqEquality,  intEquality,  isect_memberEquality,  voidElimination,  voidEquality,  independent_pairFormation,  functionExtensionality,  dependent_set_memberEquality,  because_Cache,  instantiate,  productEquality,  equalityTransitivity,  equalitySymmetry,  applyLambdaEquality

Latex:
\mforall{}[T:Type]
    \mforall{}L:T  List
        \mforall{}[P:\mBbbN{}||L||  {}\mrightarrow{}  \mBbbP{}]
            ((\mforall{}x:\mBbbN{}||L||.  Dec(P  x))
            {}\mRightarrow{}  (\mexists{}i:\mBbbN{}||L||.  (P  i))
            {}\mRightarrow{}  (\mexists{}i:\mBbbN{}||L||.  ((P  i)  \mwedge{}  (\mforall{}j:\mBbbN{}||L||.  \mneg{}(P  j)  supposing  i  <  j))))



Date html generated: 2019_10_15-AM-10_57_23
Last ObjectModification: 2018_09_17-PM-06_30_33

Theory : list!


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