Nuprl Lemma : cons-has-member

∀[S:Type]. ∀a:S. ∀[b:S List]. ∃x:S. (x ∈ [a / b])


Proof




Definitions occuring in Statement :  l_member: (x ∈ l),  cons: [a / b],  list: T List,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  member: t ∈ T,  l_member: (x ∈ l),  nat: ℕ,  le: A ≤ B,  and: P ∧ Q,  less_than': less_than'(a;b),  false: False,  not: ¬A,  implies: P ⇒ Q,  top: Top,  select: L[n],  cons: [a / b],  cand: A c∧ B,  nat_plus: ℕ+,  less_than: a < b,  squash: ↓T,  true: True,  guard: {T},  uimplies: b supposing a,  sq_stable: SqStable(P),  prop: ℙ
Lemmas referenced :  istype-false,  istype-le,  length_of_cons_lemma,  istype-void,  add_nat_plus,  length_wf_nat,  istype-less_than,  cons_wf,  length_wf,  select_wf,  sq_stable__le,  l_member_wf,  list_wf,  istype-universe
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  Error :isect_memberFormation_alt,  Error :lambdaFormation_alt,  Error :dependent_pairFormation_alt,  hypothesisEquality,  Error :dependent_set_memberEquality_alt,  natural_numberEquality,  sqequalRule,  independent_pairFormation,  hypothesis,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  because_Cache,  dependent_functionElimination,  Error :isect_memberEquality_alt,  voidElimination,  imageMemberEquality,  baseClosed,  Error :inhabitedIsType,  setElimination,  rename,  imageElimination,  productElimination,  Error :equalityIstype,  equalityTransitivity,  equalitySymmetry,  independent_functionElimination,  Error :productIsType,  independent_isectElimination,  Error :universeIsType,  instantiate,  universeEquality

Latex:
\mforall{}[S:Type].  \mforall{}a:S.  \mforall{}[b:S  List].  \mexists{}x:S.  (x  \mmember{}  [a  /  b])



Date html generated: 2019_06_20-PM-00_40_38
Last ObjectModification: 2019_03_06-AM-11_06_29

Theory : list_0


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