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: List int_seg: {i..j-} less_than: a < b decidable: Dec(P) uimplies: supposing a uall: [x:A]. B[x] prop: all: x:A. B[x] exists: x:A. B[x] not: ¬A implies:  Q and: P ∧ Q apply: 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:  Q member: t ∈ T exists: x:A. B[x] and: P ∧ Q prop: 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: supposing a not: ¬A satisfiable_int_formula: satisfiable_int_formula(fmla) false: False top: Top cand: c∧ B subtype_rel: A ⊆B interleaving_occurence: interleaving_occurence(T;L1;L2;L;f1;f2) nat: ge: i ≥  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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