Nuprl Lemma : longest-prefix-is-nil

[T:Type]. ∀[L:T List]. ∀[P:(T List) ⟶ 𝔹].
  ∀[L':T List]. (¬↑(P L')) supposing (L' < and [] < L') supposing longest-prefix(P;L) [] ∈ (T List)


Proof




Definitions occuring in Statement :  longest-prefix: longest-prefix(P;L) proper-iseg: L1 < L2 nil: [] list: List assert: b bool: 𝔹 uimplies: supposing a uall: [x:A]. B[x] not: ¬A apply: a function: x:A ⟶ B[x] universe: Type equal: t ∈ T
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T all: x:A. B[x] subtype_rel: A ⊆B so_lambda: λ2x.t[x] so_apply: x[s] uimplies: supposing a listp: List+ implies:  Q not: ¬A false: False and: P ∧ Q or: P ∨ Q prop: guard: {T}
Lemmas referenced :  longest-prefix_property longest-prefix_wf subtype_rel_dep_function list_wf bool_wf listp_wf subtype_rel_self assert_wf proper-iseg_wf nil_wf equal-wf-T-base iseg_wf less_than_wf length_wf or_wf length_of_nil_lemma all_wf not_wf equal_wf and_wf
Rules used in proof :  cut introduction extract_by_obid sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation hypothesis sqequalHypSubstitution isectElimination thin hypothesisEquality dependent_functionElimination cumulativity applyEquality sqequalRule lambdaEquality independent_isectElimination setElimination rename because_Cache lambdaFormation productElimination unionElimination functionExtensionality independent_functionElimination voidElimination isect_memberEquality equalityTransitivity equalitySymmetry baseClosed productEquality isectEquality natural_numberEquality applyLambdaEquality functionEquality universeEquality hyp_replacement dependent_set_memberEquality independent_pairFormation

Latex:
\mforall{}[T:Type].  \mforall{}[L:T  List].  \mforall{}[P:(T  List)  {}\mrightarrow{}  \mBbbB{}].
    \mforall{}[L':T  List].  (\mneg{}\muparrow{}(P  L'))  supposing  (L'  <  L  and  []  <  L')  supposing  longest-prefix(P;L)  =  []



Date html generated: 2018_05_21-PM-06_42_04
Last ObjectModification: 2017_07_26-PM-04_54_04

Theory : general


Home Index