Nuprl Lemma : select_tl

∀[A:Type]. ∀[as:A List]. ∀[n:ℕ||as|| - 1].  (tl(as)[n] = as[n + 1] ∈ A)


Proof




Definitions occuring in Statement :  select: L[n],  length: ||as||,  tl: tl(l),  list: T List,  int_seg: {i..j-},  uall: ∀[x:A]. B[x],  subtract: n - m,  add: n + m,  natural_number: $n,  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  so_lambda: λ2x.t[x],  int_seg: {i..j-},  uimplies: b supposing a,  sq_stable: SqStable(P),  implies: P ⇒ Q,  lelt: i ≤ j < k,  and: P ∧ Q,  squash: ↓T,  prop: ℙ,  all: ∀x:A. B[x],  ge: i ≥ j ,  decidable: Dec(P),  or: P ∨ Q,  iff: P ⇐⇒ Q,  not: ¬A,  rev_implies: P ⇐ Q,  false: False,  uiff: uiff(P;Q),  subtract: n - m,  subtype_rel: A ⊆r B,  top: Top,  le: A ≤ B,  less_than': less_than'(a;b),  true: True,  guard: {T},  so_apply: x[s],  select: L[n],  nil: [],  it: ⋅,  so_lambda: λ2x y.t[x; y],  so_apply: x[s1;s2]
Lemmas referenced :  add-subtract-cancel,  select-cons-tl,  reduce_tl_cons_lemma,  length_of_cons_lemma,  le-add-cancel2,  base_wf,  stuck-spread,  reduce_tl_nil_lemma,  length_of_nil_lemma,  list_wf,  not-lt-2,  decidable__lt,  add-zero,  not-le-2,  iff_weakening_equal,  le-add-cancel,  add_functionality_wrt_le,  zero-add,  add-commutes,  minus-one-mul-top,  add-swap,  minus-one-mul,  minus-add,  add-associates,  condition-implies-le,  less-iff-le,  not-ge-2,  false_wf,  decidable__le,  length_tl,  true_wf,  squash_wf,  less_than_wf,  sq_stable__le,  tl_wf,  select_wf,  equal_wf,  length_wf,  subtract_wf,  int_seg_wf,  uall_wf,  list_induction
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  thin,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  hypothesisEquality,  sqequalRule,  lambdaEquality,  natural_numberEquality,  cumulativity,  hypothesis,  because_Cache,  setElimination,  rename,  independent_isectElimination,  independent_functionElimination,  productElimination,  imageMemberEquality,  baseClosed,  imageElimination,  applyEquality,  equalityTransitivity,  equalitySymmetry,  intEquality,  dependent_functionElimination,  unionElimination,  independent_pairFormation,  lambdaFormation,  voidElimination,  addEquality,  minusEquality,  isect_memberEquality,  voidEquality,  universeEquality,  axiomEquality

Latex:
\mforall{}[A:Type].  \mforall{}[as:A  List].  \mforall{}[n:\mBbbN{}||as||  -  1].    (tl(as)[n]  =  as[n  +  1])



Date html generated: 2016_05_14-AM-06_36_37
Last ObjectModification: 2016_01_06-PM-08_33_28

Theory : list_0


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