Nuprl Lemma : dlattice-order-iff

∀[X:Type]. ∀as,bs:X List List.  (as ⇒ bs ⇐⇒ ∀x:X List. ((x ∈ bs) ⇒ (∃y:X List. ((y ∈ as) ∧ l_subset(X;y;x)))))


Proof




Definitions occuring in Statement :  dlattice-order: as ⇒ bs,  l_subset: l_subset(T;as;bs),  l_member: (x ∈ l),  list: T List,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  iff: P ⇐⇒ Q,  implies: P ⇒ Q,  and: P ∧ Q,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  and: P ∧ Q,  implies: P ⇒ Q,  member: t ∈ T,  prop: ℙ,  rev_implies: P ⇐ Q,  so_lambda: λ2x.t[x],  so_apply: x[s],  dlattice-order: as ⇒ bs,  exists: ∃x:A. B[x],  cand: A c∧ B
Lemmas referenced :  l_member_wf,  list_wf,  dlattice-order_wf,  all_wf,  exists_wf,  l_subset_wf,  l_all_iff,  l_exists_wf,  l_contains_wf,  l_exists_iff,  l_subset-l_contains
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  independent_pairFormation,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  cumulativity,  hypothesisEquality,  hypothesis,  sqequalRule,  lambdaEquality,  functionEquality,  productEquality,  universeEquality,  dependent_functionElimination,  setElimination,  rename,  setEquality,  productElimination,  independent_functionElimination,  dependent_pairFormation,  addLevel,  allFunctionality,  impliesFunctionality,  levelHypothesis,  allLevelFunctionality,  impliesLevelFunctionality

Latex:
\mforall{}[X:Type]
    \mforall{}as,bs:X  List  List.
        (as  {}\mRightarrow{}  bs  \mLeftarrow{}{}\mRightarrow{}  \mforall{}x:X  List.  ((x  \mmember{}  bs)  {}\mRightarrow{}  (\mexists{}y:X  List.  ((y  \mmember{}  as)  \mwedge{}  l\_subset(X;y;x)))))



Date html generated: 2020_05_20-AM-08_26_30
Last ObjectModification: 2017_07_28-AM-09_13_17

Theory : lattices


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