Nuprl Lemma : before-adjacent

∀[T:Type]
  ∀L:T List. ∀x,y:T.
    adjacent(T;L;x;y) ⇒ (∀z:T. (z before y ∈ L ⇒ (z before x ∈ L ∨ (z = x ∈ T)))) supposing no_repeats(T;L)


Proof




Definitions occuring in Statement :  adjacent: adjacent(T;L;x;y),  l_before: x before y ∈ l,  no_repeats: no_repeats(T;l),  list: T List,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  implies: P ⇒ Q,  or: P ∨ Q,  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  member: t ∈ T,  so_lambda: λ2x.t[x],  uimplies: b supposing a,  prop: ℙ,  implies: P ⇒ Q,  or: P ∨ Q,  so_apply: x[s],  false: False,  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  guard: {T},  uiff: uiff(P;Q),  squash: ↓T,  true: True,  subtype_rel: A ⊆r B,  not: ¬A,  cand: A c∧ B
Lemmas referenced :  list_induction,  all_wf,  isect_wf,  no_repeats_wf,  adjacent_wf,  l_before_wf,  or_wf,  equal_wf,  list_wf,  no_repeats_witness,  nil_wf,  cons_wf,  adjacent-nil,  adjacent-cons,  cons_before,  l_member_wf,  no_repeats_cons,  hd-before,  l_before_member2,  no_repeats_iff,  not_wf,  squash_wf,  true_wf,  iff_weakening_equal,  l_before_antisymmetry,  adjacent-member
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  cut,  thin,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  hypothesisEquality,  sqequalRule,  lambdaEquality,  cumulativity,  because_Cache,  hypothesis,  functionEquality,  independent_functionElimination,  rename,  dependent_functionElimination,  universeEquality,  independent_isectElimination,  voidElimination,  productElimination,  unionElimination,  addLevel,  orFunctionality,  productEquality,  inrFormation,  equalityTransitivity,  equalitySymmetry,  applyEquality,  imageElimination,  natural_numberEquality,  imageMemberEquality,  baseClosed,  hyp_replacement,  applyLambdaEquality,  inlFormation,  independent_pairFormation

Latex:
\mforall{}[T:Type]
    \mforall{}L:T  List.  \mforall{}x,y:T.
        adjacent(T;L;x;y)  {}\mRightarrow{}  (\mforall{}z:T.  (z  before  y  \mmember{}  L  {}\mRightarrow{}  (z  before  x  \mmember{}  L  \mvee{}  (z  =  x)))) 
        supposing  no\_repeats(T;L)



Date html generated: 2018_05_21-PM-06_39_31
Last ObjectModification: 2017_07_26-PM-04_53_27

Theory : general


Home Index