Nuprl Lemma : ratio-test-corollary

∀x:ℕ ⟶ ℝ
  ((∀n:ℕ. x[n] ≠ r0) ⇒ (∀L:ℝ. (lim n→∞.|(x[n + 1]/x[n])| = L ⇒ (((L < r1) ⇒ Σn.x[n]↓) ∧ ((r1 < L) ⇒ Σn.x[n]↑)))))


Proof




Definitions occuring in Statement :  series-diverges: Σn.x[n]↑,  series-converges: Σn.x[n]↓,  converges-to: lim n→∞.x[n] = y,  rdiv: (x/y),  rneq: x ≠ y,  rless: x < y,  rabs: |x|,  int-to-real: r(n),  real: ℝ,  nat: ℕ,  so_apply: x[s],  all: ∀x:A. B[x],  implies: P ⇒ Q,  and: P ∧ Q,  function: x:A ⟶ B[x],  add: n + m,  natural_number: $n
Definitions unfolded in proof :  all: ∀x:A. B[x],  member: t ∈ T,  implies: P ⇒ Q,  and: P ∧ Q,  cand: A c∧ B,  prop: ℙ,  uall: ∀[x:A]. B[x],  so_lambda: λ2x.t[x],  so_apply: x[s],  nat: ℕ,  ge: i ≥ j ,  decidable: Dec(P),  or: P ∨ Q,  uimplies: b supposing a,  not: ¬A,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  top: Top,  rneq: x ≠ y,  guard: {T},  uiff: uiff(P;Q),  req_int_terms: t1 ≡ t2,  rless: x < y,  sq_exists: ∃x:A [B[x]],  nat_plus: ℕ+,  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  subtype_rel: A ⊆r B,  real: ℝ,  sq_stable: SqStable(P),  squash: ↓T,  rdiv: (x/y),  rev_uimplies: rev_uimplies(P;Q),  rge: x ≥ y,  converges-to: lim n→∞.x[n] = y,  rleq: x ≤ y,  rnonneg: rnonneg(x),  le: A ≤ B,  int_upper: {i...},  itermConstant: "const",  true: True,  less_than': less_than'(a;b),  subtract: n - m
Lemmas referenced :  ratio-test-ext,  rless_wf,  int-to-real_wf,  converges-to_wf,  rabs_wf,  rdiv_wf,  nat_wf,  nat_properties,  decidable__le,  full-omega-unsat,  intformand_wf,  intformnot_wf,  intformle_wf,  itermConstant_wf,  itermAdd_wf,  itermVar_wf,  int_formula_prop_and_lemma,  int_formula_prop_not_lemma,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_term_value_add_lemma,  int_term_value_var_lemma,  int_formula_prop_wf,  le_wf,  real_wf,  all_wf,  rneq_wf,  small-reciprocal-real,  rless-implies-rless,  rsub_wf,  itermSubtract_wf,  req-iff-rsub-is-0,  real_polynomial_null,  real_term_value_sub_lemma,  real_term_value_const_lemma,  real_term_value_var_lemma,  zero-rleq-rabs,  sq_stable__less_than,  rless-int,  nat_plus_properties,  decidable__lt,  satisfiable-full-omega-tt,  intformless_wf,  int_formula_prop_less_lemma,  constant-rleq-limit,  radd-preserves-rless,  radd_wf,  rmul_wf,  rinv_wf2,  itermMultiply_wf,  rless_functionality,  req_transitivity,  radd_functionality,  req_weakening,  rinv-as-rdiv,  real_term_value_add_lemma,  real_term_value_mul_lemma,  trivial-rleq-radd,  rleq-int-fractions2,  int_term_value_mul_lemma,  rleq_functionality_wrt_implies,  rleq_weakening_equal,  radd_functionality_wrt_rleq,  sq_stable__all,  rleq_wf,  sq_stable__rleq,  less_than'_wf,  nat_plus_wf,  squash_wf,  int_upper_wf,  upper_subtype_nat,  sq_stable__le,  int_upper_properties,  rpositive-rless,  rabs-positive,  rabs-difference-bound-rleq,  rleq_functionality,  rabs_functionality,  rsub_functionality,  rabs-rdiv,  rmul_preserves_rleq2,  rleq_weakening_rless,  equal_wf,  rmul_comm,  rleq-implies-rleq,  rmul_functionality,  radd_comm,  rmul-rinv3,  real_term_polynomial,  less_than_wf,  le-add-cancel,  add-zero,  add-associates,  add_functionality_wrt_le,  add-commutes,  minus-one-mul-top,  zero-add,  minus-one-mul,  minus-add,  condition-implies-le,  less-iff-le,  not-lt-2,  false_wf,  int_upper_subtype_nat,  rless-int-fractions,  rminus_wf,  itermMinus_wf,  real_term_value_minus_lemma,  rmul_preserves_rless,  rless_transitivity2,  radd-preserves-rleq
Rules used in proof :  cut,  introduction,  extract_by_obid,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  hypothesis,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  hypothesisEquality,  isectElimination,  natural_numberEquality,  independent_pairFormation,  sqequalRule,  lambdaEquality,  applyEquality,  functionExtensionality,  dependent_set_memberEquality,  addEquality,  setElimination,  rename,  unionElimination,  independent_isectElimination,  approximateComputation,  independent_functionElimination,  dependent_pairFormation,  int_eqEquality,  intEquality,  isect_memberEquality,  voidElimination,  voidEquality,  because_Cache,  functionEquality,  productElimination,  inrFormation,  computeAll,  imageMemberEquality,  baseClosed,  imageElimination,  multiplyEquality,  equalityTransitivity,  equalitySymmetry,  independent_pairEquality,  minusEquality,  axiomEquality,  productEquality,  isect_memberFormation

Latex:
\mforall{}x:\mBbbN{}  {}\mrightarrow{}  \mBbbR{}
    ((\mforall{}n:\mBbbN{}.  x[n]  \mneq{}  r0)
    {}\mRightarrow{}  (\mforall{}L:\mBbbR{}.  (lim  n\mrightarrow{}\minfty{}.|(x[n  +  1]/x[n])|  =  L  {}\mRightarrow{}  (((L  <  r1)  {}\mRightarrow{}  \mSigma{}n.x[n]\mdownarrow{})  \mwedge{}  ((r1  <  L)  {}\mRightarrow{}  \mSigma{}n.x[n]\muparrow{})))))



Date html generated: 2019_10_29-AM-10_27_03
Last ObjectModification: 2018_08_23-AM-11_25_24

Theory : reals


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