Nuprl Lemma : absval_strict_ubound

∀[i:ℤ]. ∀[n:ℕ].  uiff(|i| < n;-n < i ∧ i < n)


Proof




Definitions occuring in Statement :  absval: |i|,  nat: ℕ,  less_than: a < b,  uiff: uiff(P;Q),  uall: ∀[x:A]. B[x],  and: P ∧ Q,  minus: -n,  int: ℤ
Definitions unfolded in proof :  subtract: n - m,  decidable: Dec(P),  le: A ≤ B,  rev_implies: P ⇐ Q,  iff: P ⇐⇒ Q,  assert: ↑b,  ifthenelse: if b then t else f fi ,  bnot: ¬bb,  guard: {T},  sq_type: SQType(T),  or: P ∨ Q,  exists: ∃x:A. B[x],  bfalse: ff,  false: False,  not: ¬A,  squash: ↓T,  true: True,  less_than': less_than'(a;b),  less_than: a < b,  btrue: tt,  it: ⋅,  unit: Unit,  bool: 𝔹,  implies: P ⇒ Q,  uiff: uiff(P;Q),  prop: ℙ,  and: P ∧ Q,  subtype_rel: A ⊆r B,  top: Top,  all: ∀x:A. B[x],  uimplies: b supposing a,  ge: i ≥ j ,  nat: ℕ,  member: t ∈ T,  uall: ∀[x:A]. B[x]
Lemmas referenced :  subtract_wf,  less_than_transitivity1,  one-mul,  mul-distributes-right,  mul-commutes,  le_wf,  mul_preserves_le,  le-add-cancel,  minus-add,  condition-implies-le,  less-iff-le,  not-le-2,  decidable__le,  add-zero,  add_functionality_wrt_lt,  le-add-cancel-alt,  add-swap,  add-commutes,  add-associates,  false_wf,  minus-one-mul-top,  decidable__lt,  not-lt-2,  assert_of_bnot,  iff_weakening_uiff,  not_wf,  bnot_wf,  assert_wf,  iff_transitivity,  bool_subtype_base,  subtype_base_sq,  bool_cases_sqequal,  equal_wf,  eqff_to_assert,  top_wf,  assert_of_lt_int,  eqtt_to_assert,  bool_wf,  lt_int_wf,  zero-mul,  add-mul-special,  zero-add,  minus-one-mul,  member-less_than,  nat_wf,  absval_wf,  less_than_wf,  le_reflexive,  add_functionality_wrt_le,  nat_properties,  absval_unfold
Rules used in proof :  dependent_set_memberEquality,  addEquality,  impliesFunctionality,  cumulativity,  instantiate,  promote_hyp,  dependent_pairFormation,  independent_functionElimination,  imageElimination,  baseClosed,  imageMemberEquality,  independent_pairFormation,  sqequalAxiom,  lessCases,  equalityElimination,  unionElimination,  lambdaFormation,  equalitySymmetry,  equalityTransitivity,  independent_pairEquality,  isect_memberFormation,  intEquality,  productEquality,  productElimination,  lambdaEquality,  applyEquality,  voidEquality,  voidElimination,  isect_memberEquality,  multiplyEquality,  dependent_functionElimination,  independent_isectElimination,  because_Cache,  minusEquality,  natural_numberEquality,  rename,  setElimination,  hypothesis,  hypothesisEquality,  thin,  isectElimination,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalHypSubstitution,  extract_by_obid,  introduction,  cut,  sqequalRule,  sqequalSubstitution

Latex:
\mforall{}[i:\mBbbZ{}].  \mforall{}[n:\mBbbN{}].    uiff(|i|  <  n;-n  <  i  \mwedge{}  i  <  n)



Date html generated: 2017_09_29-PM-05_47_06
Last ObjectModification: 2017_09_12-PM-00_00_09

Theory : arithmetic


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