Nuprl Lemma : fset-closure-exists

∀[T:Type]
  ∀eq:EqDecider(T). ∀r:T ⟶ ℕ. ∀fs:(T ⟶ T) List.
    ∀s:fset(T). ∃c:fset(T). (c = fs closure of s) supposing (∀f∈fs.∀x:T. ((¬((f x) = x ∈ T)) ⇒ r (f x) < r x))


Proof




Definitions occuring in Statement :  fset-closure: (c = fs closure of s),  fset: fset(T),  l_all: (∀x∈L.P[x]),  list: T List,  deq: EqDecider(T),  nat: ℕ,  less_than: a < b,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  not: ¬A,  implies: P ⇒ Q,  apply: f a,  function: x:A ⟶ B[x],  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  uimplies: b supposing a,  member: t ∈ T,  l_all: (∀x∈L.P[x]),  implies: P ⇒ Q,  int_seg: {i..j-},  guard: {T},  lelt: i ≤ j < k,  and: P ∧ Q,  decidable: Dec(P),  or: P ∨ Q,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  not: ¬A,  top: Top,  prop: ℙ,  less_than: a < b,  squash: ↓T,  subtype_rel: A ⊆r B,  so_lambda: λ2x.t[x],  so_apply: x[s],  nat: ℕ,  fset-closure: (c = fs closure of s),  cand: A c∧ B,  fset-closed: (s closed under fs),  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  true: True,  ge: i ≥ j ,  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  band: p ∧b q,  ifthenelse: if b then t else f fi ,  uiff: uiff(P;Q),  deq: EqDecider(T),  bfalse: ff,  le: A ≤ B,  sq_stable: SqStable(P),  eqof: eqof(d),  f-subset: xs ⊆ ys,  rev_uimplies: rev_uimplies(P;Q)
Lemmas referenced :  member-less_than,  select_wf,  int_seg_properties,  length_wf,  decidable__le,  satisfiable-full-omega-tt,  intformand_wf,  intformnot_wf,  intformle_wf,  itermConstant_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_var_lemma,  int_formula_prop_wf,  decidable__lt,  intformless_wf,  int_formula_prop_less_lemma,  not_wf,  equal_wf,  int_seg_wf,  decidable-equal-deq,  fset_wf,  l_all_wf,  all_wf,  less_than_wf,  l_member_wf,  list_wf,  nat_wf,  deq_wf,  fset-member_wf,  le_wf,  subtract_wf,  exists_wf,  fset-closure_wf,  set_wf,  primrec-wf2,  fset-closed_wf,  f-subset_wf,  f-subset_weakening,  l_all_iff,  isect_wf,  squash_wf,  true_wf,  iff_weakening_equal,  fset-member_witness,  nat_properties,  fset-union_wf,  fset-filter_wf,  le_int_wf,  fset-list-union_wf,  map_wf,  fset-image_wf,  eq_int_wf,  bool_wf,  eqtt_to_assert,  assert_of_eq_int,  bnot_wf,  member-fset-union,  band_wf,  less_than'_wf,  member-fset-filter,  assert_of_le_int,  member-fset-list-union,  l_exists_iff,  member_map,  member-fset-image-iff,  sq_stable__le,  assert_wf,  eqof_wf,  equal-wf-T-base,  int_subtype_base,  iff_transitivity,  iff_weakening_uiff,  assert_of_band,  assert_of_bnot,  safe-assert-deq,  itermSubtract_wf,  intformeq_wf,  int_term_value_subtract_lemma,  int_formula_prop_eq_lemma,  f-subset-union,  member-fset-image,  decidable__equal_int,  sq_stable__fset-member,  and_wf,  fset-max_wf,  fset-max_property
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  cut,  introduction,  sqequalRule,  sqequalHypSubstitution,  lambdaEquality,  dependent_functionElimination,  thin,  hypothesisEquality,  extract_by_obid,  isectElimination,  applyEquality,  functionExtensionality,  cumulativity,  functionEquality,  because_Cache,  setElimination,  rename,  hypothesis,  independent_isectElimination,  natural_numberEquality,  productElimination,  unionElimination,  dependent_pairFormation,  int_eqEquality,  intEquality,  isect_memberEquality,  voidElimination,  voidEquality,  independent_pairFormation,  computeAll,  imageElimination,  independent_functionElimination,  setEquality,  universeEquality,  equalityTransitivity,  equalitySymmetry,  imageMemberEquality,  baseClosed,  applyLambdaEquality,  equalityElimination,  independent_pairEquality,  axiomEquality,  promote_hyp,  hyp_replacement,  productEquality,  impliesFunctionality,  inlFormation,  inrFormation,  addLevel,  dependent_set_memberEquality

Latex:
\mforall{}[T:Type]
    \mforall{}eq:EqDecider(T).  \mforall{}r:T  {}\mrightarrow{}  \mBbbN{}.  \mforall{}fs:(T  {}\mrightarrow{}  T)  List.
        \mforall{}s:fset(T).  \mexists{}c:fset(T).  (c  =  fs  closure  of  s) 
        supposing  (\mforall{}f\mmember{}fs.\mforall{}x:T.  ((\mneg{}((f  x)  =  x))  {}\mRightarrow{}  r  (f  x)  <  r  x))



Date html generated: 2017_04_17-AM-09_21_56
Last ObjectModification: 2017_02_27-PM-05_26_08

Theory : finite!sets


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