Nuprl Lemma : nth_tl_nil

∀[n:ℤ]. (nth_tl(n;[]) ~ [])


Proof




Definitions occuring in Statement :  nth_tl: nth_tl(n;as),  nil: [],  uall: ∀[x:A]. B[x],  int: ℤ,  sqequal: s ~ t
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  nth_tl: nth_tl(n;as),  le_int: i ≤z j,  lt_int: i <z j,  bnot: ¬bb,  ifthenelse: if b then t else f fi ,  bfalse: ff,  btrue: tt,  subtype_rel: A ⊆r B,  uimplies: b supposing a,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  implies: P ⇒ Q,  not: ¬A,  all: ∀x:A. B[x],  top: Top,  and: P ∧ Q,  prop: ℙ,  bool: 𝔹,  unit: Unit,  it: ⋅,  uiff: uiff(P;Q),  guard: {T}
Lemmas referenced :  le_int_wf,  bool_wf,  equal-wf-base,  int_subtype_base,  assert_wf,  le_wf,  lt_int_wf,  less_than_wf,  bnot_wf,  satisfiable-full-omega-tt,  intformand_wf,  intformless_wf,  itermConstant_wf,  itermVar_wf,  int_formula_prop_and_lemma,  int_formula_prop_less_lemma,  int_term_value_constant_lemma,  int_term_value_var_lemma,  int_formula_prop_wf,  reduce_tl_nil_lemma,  uiff_transitivity,  eqtt_to_assert,  assert_of_le_int,  eqff_to_assert,  assert_functionality_wrt_uiff,  bnot_of_le_int,  assert_of_lt_int,  equal_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  intWeakElimination,  sqequalHypSubstitution,  thin,  rename,  hypothesis,  sqequalRule,  sqequalAxiom,  axiomEquality,  equalityTransitivity,  equalitySymmetry,  intEquality,  extract_by_obid,  isectElimination,  hypothesisEquality,  natural_numberEquality,  baseApply,  closedConclusion,  baseClosed,  applyEquality,  because_Cache,  independent_isectElimination,  dependent_pairFormation,  lambdaEquality,  int_eqEquality,  dependent_functionElimination,  isect_memberEquality,  voidElimination,  voidEquality,  independent_pairFormation,  computeAll,  lambdaFormation,  unionElimination,  equalityElimination,  independent_functionElimination,  productElimination

Latex:
\mforall{}[n:\mBbbZ{}].  (nth\_tl(n;[])  \msim{}  [])



Date html generated: 2017_04_14-AM-09_25_07
Last ObjectModification: 2017_02_27-PM-03_59_30

Theory : list_1


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