Nuprl Lemma : mem_iff_mem_f

∀s:DSet. ∀a:|s|. ∀bs:|s| List.  (↑(a ∈b bs) ⇐⇒ mem_f(|s|;a;bs))


Proof




Definitions occuring in Statement :  mem: a ∈b as,  mem_f: mem_f(T;a;bs),  list: T List,  assert: ↑b,  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  dset: DSet,  set_car: |p|
Definitions unfolded in proof :  all: ∀x:A. B[x],  uall: ∀[x:A]. B[x],  member: t ∈ T,  so_lambda: λ2x.t[x],  dset: DSet,  so_apply: x[s],  implies: P ⇒ Q,  top: Top,  mem_f: mem_f(T;a;bs),  ycomb: Y,  so_lambda: so_lambda(x,y,z.t[x; y; z]),  so_apply: x[s1;s2;s3],  assert: ↑b,  ifthenelse: if b then t else f fi ,  bfalse: ff,  iff: P ⇐⇒ Q,  and: P ∧ Q,  false: False,  rev_implies: P ⇐ Q,  prop: ℙ,  or: P ∨ Q,  infix_ap: x f y
Lemmas referenced :  list_induction,  iff_wf,  assert_wf,  mem_wf,  mem_f_wf,  set_car_wf,  mem_nil_lemma,  istype-void,  list_ind_nil_lemma,  mem_cons_lemma,  list_ind_cons_lemma,  list_wf,  dset_wf,  bor_wf,  set_eq_wf,  or_wf,  equal_wf,  iff_transitivity,  iff_weakening_uiff,  assert_of_bor,  assert_of_dset_eq
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation_alt,  cut,  thin,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  because_Cache,  sqequalRule,  lambdaEquality_alt,  dependent_functionElimination,  hypothesisEquality,  hypothesis,  setElimination,  rename,  universeIsType,  independent_functionElimination,  isect_memberEquality_alt,  voidElimination,  independent_pairFormation,  productIsType,  functionIsType,  inhabitedIsType,  productElimination,  unionIsType,  equalityIsType1,  unionElimination,  inlFormation_alt,  inrFormation_alt,  promote_hyp,  applyEquality

Latex:
\mforall{}s:DSet.  \mforall{}a:|s|.  \mforall{}bs:|s|  List.    (\muparrow{}(a  \mmember{}\msubb{}  bs)  \mLeftarrow{}{}\mRightarrow{}  mem\_f(|s|;a;bs))



Date html generated: 2019_10_16-PM-01_03_24
Last ObjectModification: 2018_10_08-AM-11_21_53

Theory : list_2


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