Nuprl Lemma : test-recursion-extract

∀k:ℕ. ∀f:ℕ ⟶ ℚ.  ((∃n:ℕk. ((f n) = 0 ∈ ℚ)) ∨ True)


Proof




Definitions occuring in Statement :  rationals: ℚ,  int_seg: {i..j-},  nat: ℕ,  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  or: P ∨ Q,  true: True,  apply: f a,  function: x:A ⟶ B[x],  natural_number: $n,  equal: s = t ∈ T
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  uall: ∀[x:A]. B[x],  nat: ℕ,  or: P ∨ Q,  exists: ∃x:A. B[x],  int_seg: {i..j-},  subtype_rel: A ⊆r B,  uimplies: b supposing a,  le: A ≤ B,  and: P ∧ Q,  less_than': less_than'(a;b),  false: False,  not: ¬A,  prop: ℙ,  so_lambda: λ2x.t[x],  so_apply: x[s],  so_lambda: λ2x y.t[x; y],  so_apply: x[s1;s2],  squash: ↓T,  decidable: Dec(P),  sq_type: SQType(T),  guard: {T},  true: True,  ge: i ≥ j ,  lelt: i ≤ j < k,  satisfiable_int_formula: satisfiable_int_formula(fmla),  top: Top,  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  uiff: uiff(P;Q),  ifthenelse: if b then t else f fi ,  nequal: a ≠ b ∈ T ,  int_upper: {i...},  bfalse: ff,  bnot: ¬bb,  assert: ↑b,  rev_implies: P ⇐ Q,  iff: P ⇐⇒ Q
Lemmas referenced :  int_seg_wf,  rationals_wf,  int_seg_subtype_nat,  istype-false,  true_wf,  istype-nat,  natrec_wf,  all_wf,  nat_wf,  or_wf,  exists_wf,  equal-wf-T-base,  subtype_rel_function,  subtype_rel_self,  function-valueall-type,  rationals-value-type,  evalall-reduce,  set-value-type,  equal_wf,  valueall-type-value-type,  decidable__equal_int,  subtype_base_sq,  int_subtype_base,  int_seg_properties,  nat_properties,  full-omega-unsat,  intformand_wf,  intformless_wf,  itermVar_wf,  itermConstant_wf,  intformle_wf,  istype-int,  int_formula_prop_and_lemma,  istype-void,  int_formula_prop_less_lemma,  int_term_value_var_lemma,  int_term_value_constant_lemma,  int_formula_prop_le_lemma,  int_formula_prop_wf,  decidable__equal_rationals,  subtract_wf,  decidable__le,  intformnot_wf,  itermSubtract_wf,  intformeq_wf,  int_formula_prop_not_lemma,  int_term_value_subtract_lemma,  int_formula_prop_eq_lemma,  le_wf,  int-subtype-rationals,  decidable__lt,  less_than_wf,  lt_int_wf,  eqtt_to_assert,  assert_of_lt_int,  upper_subtype_nat,  nequal-le-implies,  zero-add,  eqff_to_assert,  bool_cases_sqequal,  bool_wf,  bool_subtype_base,  assert-bnot,  iff_weakening_uiff,  assert_wf,  qexp_wf,  bnot_wf,  not_wf,  bool_cases,  iff_transitivity,  assert_of_bnot
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation_alt,  cut,  thin,  sqequalRule,  functionIsType,  universeIsType,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  natural_numberEquality,  setElimination,  rename,  hypothesisEquality,  hypothesis,  inhabitedIsType,  unionIsType,  productIsType,  equalityIsType3,  applyEquality,  independent_isectElimination,  independent_pairFormation,  baseClosed,  lambdaEquality_alt,  functionEquality,  because_Cache,  functionExtensionality,  dependent_functionElimination,  imageMemberEquality,  equalityTransitivity,  equalitySymmetry,  cutEval,  dependent_set_memberEquality_alt,  equalityIsType1,  hyp_replacement,  applyLambdaEquality,  unionElimination,  instantiate,  cumulativity,  intEquality,  independent_functionElimination,  inrFormation_alt,  productElimination,  approximateComputation,  dependent_pairFormation_alt,  int_eqEquality,  isect_memberEquality_alt,  voidElimination,  inlFormation_alt,  equalityElimination,  hypothesis_subsumption,  equalityIsType2,  baseApply,  closedConclusion,  promote_hyp

Latex:
\mforall{}k:\mBbbN{}.  \mforall{}f:\mBbbN{}  {}\mrightarrow{}  \mBbbQ{}.    ((\mexists{}n:\mBbbN{}k.  ((f  n)  =  0))  \mvee{}  True)



Date html generated: 2019_10_16-PM-00_34_09
Last ObjectModification: 2018_10_10-AM-11_04_51

Theory : rationals


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