Nuprl Lemma : select-reverse

∀[T:Type]. ∀[L:T List]. ∀[i:ℕ||rev(L)||].  (rev(L)[i] = L[||L|| - 1 - i] ∈ T)


Proof




Definitions occuring in Statement :  select: L[n],  length: ||as||,  reverse: rev(as),  list: T List,  int_seg: {i..j-},  uall: ∀[x:A]. B[x],  subtract: n - m,  natural_number: $n,  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  reverse: rev(as),  top: Top,  squash: ↓T,  prop: ℙ,  int_seg: {i..j-},  lelt: i ≤ j < k,  and: P ∧ Q,  le: A ≤ B,  less_than: a < b,  uimplies: b supposing a,  all: ∀x:A. B[x],  implies: P ⇒ Q,  exists: ∃x:A. B[x],  subtype_rel: A ⊆r B,  nat: ℕ,  so_lambda: λ2x.t[x],  so_apply: x[s],  true: True,  guard: {T},  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  uiff: uiff(P;Q),  ifthenelse: if b then t else f fi ,  bfalse: ff,  or: P ∨ Q,  sq_type: SQType(T),  bnot: ¬bb,  assert: ↑b,  false: False,  not: ¬A,  select: L[n],  nil: [],  so_lambda: λ2x y.t[x; y],  so_apply: x[s1;s2],  subtract: n - m,  nat_plus: ℕ+,  less_than': less_than'(a;b),  decidable: Dec(P)
Lemmas referenced :  length-reverse,  equal_wf,  squash_wf,  true_wf,  select-rev-append,  nil_wf,  length-nil,  add-zero,  length_wf,  lelt_wf,  select_wf,  subtract_wf,  non_neg_length,  length_wf_nat,  nat_wf,  set_subtype_base,  le_wf,  int_subtype_base,  iff_weakening_equal,  lt_int_wf,  bool_wf,  eqtt_to_assert,  assert_of_lt_int,  eqff_to_assert,  bool_cases_sqequal,  subtype_base_sq,  bool_subtype_base,  assert-bnot,  less_than_wf,  stuck-spread,  base_wf,  int_seg_wf,  reverse_wf,  add-associates,  minus-one-mul,  add-swap,  add-commutes,  less-iff-le,  add_functionality_wrt_le,  le_reflexive,  minus-one-mul-top,  one-mul,  add-mul-special,  two-mul,  mul-distributes-right,  zero-mul,  not-le-2,  minus-zero,  zero-add,  omega-shadow,  mul-distributes,  mul-associates,  le-add-cancel,  not-lt-2,  minus-add,  minus-minus,  int_seg_properties,  nat_properties,  decidable__le,  decidable__lt
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  sqequalHypSubstitution,  sqequalRule,  extract_by_obid,  isectElimination,  thin,  isect_memberEquality,  voidElimination,  voidEquality,  hypothesis,  applyEquality,  lambdaEquality,  imageElimination,  hypothesisEquality,  equalityTransitivity,  equalitySymmetry,  because_Cache,  cumulativity,  setElimination,  rename,  dependent_set_memberEquality,  productElimination,  independent_pairFormation,  addEquality,  natural_numberEquality,  independent_isectElimination,  lambdaFormation,  dependent_pairFormation,  sqequalIntensionalEquality,  intEquality,  dependent_functionElimination,  independent_functionElimination,  promote_hyp,  imageMemberEquality,  baseClosed,  universeEquality,  unionElimination,  equalityElimination,  instantiate,  axiomEquality,  multiplyEquality,  minusEquality

Latex:
\mforall{}[T:Type].  \mforall{}[L:T  List].  \mforall{}[i:\mBbbN{}||rev(L)||].    (rev(L)[i]  =  L[||L||  -  1  -  i])



Date html generated: 2017_04_14-AM-08_40_31
Last ObjectModification: 2017_02_27-PM-03_31_04

Theory : list_0


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