Nuprl Lemma : l_member-permute

∀[T:Type]. ∀as,bs:T List. ∀x:T.  ((x ∈ as @ bs) ⇐⇒ (x ∈ bs @ as))


Proof




Definitions occuring in Statement :  l_member: (x ∈ l),  append: as @ bs,  list: T List,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  iff: 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,  or: P ∨ Q,  guard: {T},  member: t ∈ T,  prop: ℙ,  rev_implies: P ⇐ Q
Lemmas referenced :  l_member_wf,  or_wf,  member_append,  append_wf,  iff_wf,  list_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  cut,  independent_pairFormation,  sqequalHypSubstitution,  unionElimination,  thin,  sqequalRule,  hypothesis,  inrFormation,  introduction,  extract_by_obid,  isectElimination,  hypothesisEquality,  inlFormation,  because_Cache,  addLevel,  productElimination,  independent_functionElimination,  dependent_functionElimination,  universeEquality

Latex:
\mforall{}[T:Type].  \mforall{}as,bs:T  List.  \mforall{}x:T.    ((x  \mmember{}  as  @  bs)  \mLeftarrow{}{}\mRightarrow{}  (x  \mmember{}  bs  @  as))



Date html generated: 2019_10_15-AM-11_13_36
Last ObjectModification: 2018_08_25-PM-00_07_14

Theory : general


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