Nuprl Lemma : member-f-union

∀[T,A:Type]. ∀[eqt:EqDecider(T)]. ∀[eqa:EqDecider(A)]. ∀[g:T ⟶ fset(A)]. ∀[s:fset(T)]. ∀[a:A].
  uiff(a ∈ f-union(eqt;eqa;s;x.g[x]);↓∃x:T. (x ∈ s ∧ a ∈ g[x]))


Proof




Definitions occuring in Statement :  f-union: f-union(domeq;rngeq;s;x.g[x]),  fset-member: a ∈ s,  fset: fset(T),  deq: EqDecider(T),  uiff: uiff(P;Q),  uall: ∀[x:A]. B[x],  so_apply: x[s],  exists: ∃x:A. B[x],  squash: ↓T,  and: P ∧ Q,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uiff: uiff(P;Q),  and: P ∧ Q,  uimplies: b supposing a,  squash: ↓T,  prop: ℙ,  so_lambda: λ2x.t[x],  so_apply: x[s],  implies: P ⇒ Q,  fset: fset(T),  exists: ∃x:A. B[x],  quotient: x,y:A//B[x; y],  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  cand: A c∧ B,  subtype_rel: A ⊆r B,  guard: {T},  fset-member: a ∈ s,  rev_implies: P ⇐ Q,  decidable: Dec(P),  or: P ∨ Q,  sq_type: SQType(T),  true: True,  false: False,  not: ¬A
Lemmas referenced :  fset-member_wf,  f-union_wf,  fset-member_witness,  squash_wf,  exists_wf,  fset_wf,  deq_wf,  equal-wf-base,  list_wf,  set-equal_wf,  member-f-union-aux,  l_exists_iff,  l_member_wf,  list_subtype_fset,  assert-deq-member,  decidable__fset-member,  subtype_base_sq,  int_subtype_base,  set-equal-reflex,  equal_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  independent_pairFormation,  hypothesis,  sqequalHypSubstitution,  imageElimination,  sqequalRule,  imageMemberEquality,  hypothesisEquality,  thin,  baseClosed,  extract_by_obid,  isectElimination,  cumulativity,  lambdaEquality,  applyEquality,  functionExtensionality,  independent_functionElimination,  productEquality,  productElimination,  independent_pairEquality,  isect_memberEquality,  because_Cache,  equalityTransitivity,  equalitySymmetry,  functionEquality,  universeEquality,  pointwiseFunctionalityForEquality,  pertypeElimination,  dependent_functionElimination,  setElimination,  rename,  setEquality,  dependent_pairFormation,  independent_isectElimination,  unionElimination,  instantiate,  intEquality,  natural_numberEquality,  voidElimination,  promote_hyp,  lambdaFormation,  pointwiseFunctionality

Latex:
\mforall{}[T,A:Type].  \mforall{}[eqt:EqDecider(T)].  \mforall{}[eqa:EqDecider(A)].  \mforall{}[g:T  {}\mrightarrow{}  fset(A)].  \mforall{}[s:fset(T)].  \mforall{}[a:A].
    uiff(a  \mmember{}  f-union(eqt;eqa;s;x.g[x]);\mdownarrow{}\mexists{}x:T.  (x  \mmember{}  s  \mwedge{}  a  \mmember{}  g[x]))



Date html generated: 2017_04_17-AM-09_19_10
Last ObjectModification: 2017_02_27-PM-05_22_45

Theory : finite!sets


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