Nuprl Lemma : not-not-all-int_seg-xmiddle

∀a,b:ℤ. ∀P:{a..b-} ⟶ ℙ.  (¬¬(∀i:{a..b-}. (P[i] ∨ (¬P[i]))))


Proof




Definitions occuring in Statement :  int_seg: {i..j-},  prop: ℙ,  so_apply: x[s],  all: ∀x:A. B[x],  not: ¬A,  or: P ∨ Q,  function: x:A ⟶ B[x],  int: ℤ
Definitions unfolded in proof :  all: ∀x:A. B[x],  uall: ∀[x:A]. B[x],  member: t ∈ T,  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,  not: ¬A,  int_seg: {i..j-},  sq_stable: SqStable(P),  lelt: i ≤ j < k,  uiff: uiff(P;Q),  subtract: n - m,  top: Top,  less_than': less_than'(a;b),  true: True,  or: P ∨ Q,  so_apply: x[s],  subtype_rel: A ⊆r B,  so_lambda: λ2x.t[x],  decidable: Dec(P),  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  nat_plus: ℕ+,  sq_type: SQType(T)
Lemmas referenced :  nat_properties,  less_than_transitivity1,  less_than_irreflexivity,  ge_wf,  istype-less_than,  sq_stable__le,  less-iff-le,  condition-implies-le,  minus-add,  istype-void,  minus-one-mul,  add-swap,  minus-one-mul-top,  add-associates,  zero-add,  add_functionality_wrt_le,  add-commutes,  le-add-cancel,  int_seg_wf,  subtype_rel_self,  subtract-1-ge-0,  istype-nat,  add-is-int-iff,  int_subtype_base,  decidable__lt,  istype-false,  not-lt-2,  subtract_wf,  le-add-cancel2,  istype-le,  not-not-1-xmiddle,  add-mul-special,  zero-mul,  add-zero,  le-add-cancel-alt,  le_reflexive,  one-mul,  two-mul,  mul-distributes-right,  not-le-2,  omega-shadow,  decidable__le,  double-negation-hyp-elim,  all_wf,  or_wf,  not_wf,  subtype_base_sq,  set_subtype_base,  lelt_wf,  decidable__int_equal,  not-equal-2,  minus-minus,  subtract_nat_wf,  istype-int
Rules used in proof :  cut,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation_alt,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  hypothesis,  setElimination,  rename,  intWeakElimination,  independent_pairFormation,  productElimination,  imageElimination,  natural_numberEquality,  independent_isectElimination,  independent_functionElimination,  voidElimination,  universeIsType,  sqequalRule,  lambdaEquality_alt,  dependent_functionElimination,  functionIsTypeImplies,  inhabitedIsType,  addEquality,  isect_memberEquality_alt,  minusEquality,  imageMemberEquality,  baseClosed,  functionIsType,  unionIsType,  applyEquality,  instantiate,  universeEquality,  because_Cache,  dependent_set_memberEquality_alt,  baseApply,  closedConclusion,  unionElimination,  productIsType,  multiplyEquality,  functionEquality,  unionEquality,  cumulativity,  intEquality,  equalityTransitivity,  equalitySymmetry,  equalityIstype

Latex:
\mforall{}a,b:\mBbbZ{}.  \mforall{}P:\{a..b\msupminus{}\}  {}\mrightarrow{}  \mBbbP{}.    (\mneg{}\mneg{}(\mforall{}i:\{a..b\msupminus{}\}.  (P[i]  \mvee{}  (\mneg{}P[i]))))



Date html generated: 2020_05_19-PM-09_36_10
Last ObjectModification: 2019_10_17-PM-02_49_36

Theory : int_1


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