Nuprl Lemma : select-append

∀[L1,L2:Top List]. ∀[i:ℕ].  (L1 @ L2[i] ~ if i <z ||L1|| then L1[i] else L2[i - ||L1||] fi )


Proof




Definitions occuring in Statement :  select: L[n],  length: ||as||,  append: as @ bs,  list: T List,  nat: ℕ,  ifthenelse: if b then t else f fi ,  lt_int: i <z j,  uall: ∀[x:A]. B[x],  top: Top,  subtract: n - m,  sqequal: s ~ t
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  all: ∀x:A. B[x],  nat: ℕ,  implies: P ⇒ Q,  false: False,  and: P ∧ Q,  ge: i ≥ j ,  le: A ≤ B,  cand: A c∧ B,  less_than: a < b,  squash: ↓T,  guard: {T},  uimplies: b supposing a,  prop: ℙ,  or: P ∨ Q,  append: as @ bs,  so_lambda: so_lambda3,  so_apply: x[s1;s2;s3],  select: L[n],  nil: [],  it: ⋅,  so_lambda: λ2x y.t[x; y],  so_apply: x[s1;s2],  cons: [a / b],  less_than': less_than'(a;b),  not: ¬A,  colength: colength(L),  so_lambda: λ2x.t[x],  so_apply: x[s],  sq_type: SQType(T),  sq_stable: SqStable(P),  decidable: Dec(P),  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  uiff: uiff(P;Q),  subtract: n - m,  true: True,  subtype_rel: A ⊆r B,  bool: 𝔹,  unit: Unit,  btrue: tt,  ifthenelse: if b then t else f fi ,  bfalse: ff,  exists: ∃x:A. B[x],  bnot: ¬bb,  assert: ↑b,  nat_plus: ℕ+
Lemmas referenced :  nat_properties,  less_than_transitivity1,  less_than_irreflexivity,  ge_wf,  istype-less_than,  top_wf,  list-cases,  list_ind_nil_lemma,  length_of_nil_lemma,  stuck-spread,  istype-base,  istype-nat,  product_subtype_list,  colength-cons-not-zero,  colength_wf_list,  istype-void,  istype-le,  list_wf,  subtract-1-ge-0,  subtype_base_sq,  nat_wf,  set_subtype_base,  le_wf,  int_subtype_base,  spread_cons_lemma,  sq_stable__le,  decidable__int_equal,  subtract_wf,  istype-false,  not-equal-2,  condition-implies-le,  add-associates,  minus-add,  minus-one-mul,  add-swap,  minus-one-mul-top,  le_antisymmetry_iff,  add_functionality_wrt_le,  add-commutes,  zero-add,  le-add-cancel,  minus-minus,  list_ind_cons_lemma,  length_of_cons_lemma,  le_weakening2,  lt_int_wf,  equal-wf-base,  bool_wf,  istype-int,  assert_wf,  less_than_wf,  le_int_wf,  bnot_wf,  minus-zero,  add-zero,  uiff_transitivity,  eqtt_to_assert,  assert_of_lt_int,  eqff_to_assert,  assert_functionality_wrt_uiff,  bnot_of_lt_int,  assert_of_le_int,  length_wf,  bool_cases_sqequal,  bool_subtype_base,  assert-bnot,  iff_weakening_uiff,  non_neg_length,  length_wf_nat,  istype-sqequal,  not-lt-2,  le_reflexive,  one-mul,  add-mul-special,  two-mul,  mul-distributes-right,  zero-mul,  omega-shadow,  mul-distributes,  mul-commutes,  mul-associates,  decidable__le,  not-le-2,  less-iff-le,  add-is-int-iff,  select-cons,  bnot_of_le_int
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  thin,  lambdaFormation_alt,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  hypothesisEquality,  hypothesis,  setElimination,  rename,  intWeakElimination,  independent_pairFormation,  productElimination,  imageElimination,  natural_numberEquality,  independent_isectElimination,  independent_functionElimination,  voidElimination,  universeIsType,  sqequalRule,  lambdaEquality_alt,  dependent_functionElimination,  isect_memberEquality_alt,  axiomSqEquality,  isectIsTypeImplies,  inhabitedIsType,  functionIsTypeImplies,  unionElimination,  Error :memTop,  baseClosed,  because_Cache,  promote_hyp,  hypothesis_subsumption,  equalityIstype,  dependent_set_memberEquality_alt,  instantiate,  cumulativity,  intEquality,  equalityTransitivity,  equalitySymmetry,  imageMemberEquality,  applyLambdaEquality,  addEquality,  minusEquality,  baseApply,  closedConclusion,  applyEquality,  sqequalBase,  equalityElimination,  dependent_pairFormation_alt,  multiplyEquality

Latex:
\mforall{}[L1,L2:Top  List].  \mforall{}[i:\mBbbN{}].    (L1  @  L2[i]  \msim{}  if  i  <z  ||L1||  then  L1[i]  else  L2[i  -  ||L1||]  fi  )



Date html generated: 2020_05_19-PM-09_37_10
Last ObjectModification: 2020_03_09-PM-01_25_49

Theory : list_0


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