Nuprl Lemma : colist-unfold_wf

∀[A,B:Type]. ∀[P:B ⟶ (Unit + (A × B))]. ∀[x:B].  (colist-unfold(P;x) ∈ colist(A))


Proof




Definitions occuring in Statement :  colist-unfold: colist-unfold(P;x),  colist: colist(T),  uall: ∀[x:A]. B[x],  unit: Unit,  member: t ∈ T,  function: x:A ⟶ B[x],  product: x:A × B[x],  union: left + right,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  colist-unfold: colist-unfold(P;x),  colist: colist(T),  so_lambda: λ2x.t[x],  so_apply: x[s],  cons: [a / b],  nil: [],  isect2: T1 ⋂ T2,  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  ifthenelse: if b then t else f fi ,  top: Top,  bfalse: ff,  all: ∀x:A. B[x],  implies: P ⇒ Q,  subtype_rel: A ⊆r B,  prop: ℙ
Lemmas referenced :  unit_wf2,  fix_wf_corec_parameter,  b-union_wf,  top_wf,  it_wf,  subtype_rel_b-union-left,  subtype_rel_b-union-right,  equal_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  sqequalRule,  sqequalHypSubstitution,  hypothesis,  axiomEquality,  equalityTransitivity,  equalitySymmetry,  hypothesisEquality,  isect_memberEquality,  isectElimination,  thin,  because_Cache,  functionEquality,  cumulativity,  unionEquality,  extract_by_obid,  productEquality,  universeEquality,  lambdaEquality,  unionElimination,  equalityElimination,  functionExtensionality,  voidElimination,  voidEquality,  lambdaFormation,  applyEquality,  productElimination,  independent_pairEquality,  dependent_functionElimination,  independent_functionElimination

Latex:
\mforall{}[A,B:Type].  \mforall{}[P:B  {}\mrightarrow{}  (Unit  +  (A  \mtimes{}  B))].  \mforall{}[x:B].    (colist-unfold(P;x)  \mmember{}  colist(A))



Date html generated: 2018_05_21-PM-10_20_24
Last ObjectModification: 2017_07_26-PM-06_37_26

Theory : eval!all


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