Nuprl Lemma : unbounded-decidable-nset-infinite

∀K:Type. ((K ⊆r ℕ) ⇒ (∀l:ℕ. ((l ∈ K) ∨ (¬(l ∈ K)))) ⇒ (∀B:ℕ. ∃k:K. B < k) ⇒ (∃f:K ⟶ ℕ. Surj(K;ℕ;f)))


Proof




Definitions occuring in Statement :  surject: Surj(A;B;f),  nat: ℕ,  less_than: a < b,  subtype_rel: A ⊆r B,  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  not: ¬A,  implies: P ⇒ Q,  or: P ∨ Q,  member: t ∈ T,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  upto: upto(n),  uiff: uiff(P;Q),  nat_plus: ℕ+,  select: L[n],  l_member: (x ∈ l),  cons: [a / b],  surject: Surj(A;B;f),  respects-equality: respects-equality(S;T),  sq_type: SQType(T),  cand: A c∧ B,  squash: ↓T,  less_than: a < b,  decidable: Dec(P),  top: Top,  satisfiable_int_formula: satisfiable_int_formula(fmla),  ge: i ≥ j ,  istype: istype(T),  prop: ℙ,  less_than': less_than'(a;b),  le: A ≤ B,  guard: {T},  uimplies: b supposing a,  so_apply: x[s],  so_lambda: λ2x.t[x],  uall: ∀[x:A]. B[x],  nat: ℕ,  false: False,  not: ¬A,  bfalse: ff,  rev_implies: P ⇐ Q,  true: True,  and: P ∧ Q,  iff: P ⇐⇒ Q,  btrue: tt,  ifthenelse: if b then t else f fi ,  assert: ↑b,  isl: isl(x),  or: P ∨ Q,  subtype_rel: A ⊆r B,  member: t ∈ T,  exists: ∃x:A. B[x],  implies: P ⇒ Q,  all: ∀x:A. B[x]
Lemmas referenced :  btrue_neq_bfalse,  member-implies-null-eq-bfalse,  null_nil_lemma,  no_repeats-subtype,  no_repeats_from-upto,  no_repeats_filter,  from-upto-member-nat,  member_filter_2,  subtype_rel_sets_simple,  from-upto_wf,  length-one-iff,  subtract-add-cancel,  length-append,  filter_append_sq,  zero-le-nat,  from-upto-split,  list_subtype_base,  length_wf,  cons_wf,  false_wf,  add-is-int-iff,  nat_plus_properties,  add_nat_plus,  length_of_cons_lemma,  product_subtype_list,  nil_wf,  length_of_nil_lemma,  list-cases,  member_filter,  member_upto,  exists_wf,  decidable__equal_int,  int_formula_prop_eq_lemma,  intformeq_wf,  subtype-respects-equality,  subtype_base_sq,  le_witness_for_triv,  decidable__lt,  int_term_value_subtract_lemma,  int_formula_prop_not_lemma,  itermSubtract_wf,  intformnot_wf,  decidable__le,  equal-wf-base,  less_than_wf,  primrec-wf2,  subtract_wf,  istype-le,  int_formula_prop_wf,  int_formula_prop_less_lemma,  int_term_value_constant_lemma,  int_term_value_add_lemma,  int_term_value_var_lemma,  int_formula_prop_le_lemma,  int_formula_prop_and_lemma,  intformless_wf,  itermConstant_wf,  itermAdd_wf,  itermVar_wf,  intformle_wf,  intformand_wf,  full-omega-unsat,  nat_properties,  istype-universe,  subtype_rel_wf,  istype-less_than,  surject_wf,  istype-false,  int_seg_subtype_nat,  int_seg_wf,  subtype_rel_list,  l_member_wf,  bool_wf,  subtype_rel_dep_function,  subtype_rel_transitivity,  upto_wf,  filter_wf5,  length_wf_nat,  istype-assert,  istype-void,  int_subtype_base,  istype-int,  le_wf,  set_subtype_base,  istype-true,  istype-nat,  bfalse_wf,  btrue_wf,  nat_wf
Rules used in proof :  Error :isectIsTypeImplies,  axiomEquality,  Error :isect_memberFormation_alt,  pointwiseFunctionality,  applyLambdaEquality,  hypothesis_subsumption,  minusEquality,  baseClosed,  closedConclusion,  baseApply,  cumulativity,  promote_hyp,  imageElimination,  Error :dependent_set_memberEquality_alt,  productEquality,  functionEquality,  addEquality,  Error :isect_memberEquality_alt,  int_eqEquality,  approximateComputation,  universeEquality,  instantiate,  Error :unionIsType,  Error :setIsType,  setElimination,  setEquality,  productElimination,  Error :productIsType,  Error :functionIsType,  sqequalBase,  independent_isectElimination,  intEquality,  isectElimination,  Error :universeIsType,  voidElimination,  natural_numberEquality,  independent_pairFormation,  because_Cache,  independent_functionElimination,  dependent_functionElimination,  Error :equalityIstype,  unionElimination,  extract_by_obid,  introduction,  equalitySymmetry,  equalityTransitivity,  Error :inhabitedIsType,  thin,  hypothesis,  hypothesisEquality,  sqequalHypSubstitution,  functionExtensionality,  sqequalRule,  applyEquality,  Error :lambdaEquality_alt,  Error :dependent_pairFormation_alt,  rename,  cut,  Error :lambdaFormation_alt,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution

Latex:
\mforall{}K:Type
    ((K  \msubseteq{}r  \mBbbN{})  {}\mRightarrow{}  (\mforall{}l:\mBbbN{}.  ((l  \mmember{}  K)  \mvee{}  (\mneg{}(l  \mmember{}  K))))  {}\mRightarrow{}  (\mforall{}B:\mBbbN{}.  \mexists{}k:K.  B  <  k)  {}\mRightarrow{}  (\mexists{}f:K  {}\mrightarrow{}  \mBbbN{}.  Surj(K;\mBbbN{};f)))



Date html generated: 2019_06_20-PM-03_02_26
Last ObjectModification: 2019_06_13-PM-07_17_10

Theory : continuity


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