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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