Nuprl Lemma : permutation-filter

∀[A:Type]. ∀L1,L2:A List.  (permutation(A;L1;L2) ⇒ (∀p:A ⟶ 𝔹. permutation({a:A| ↑(p a)} ;filter(p;L1);filter(p;L2))))


Proof




Definitions occuring in Statement :  permutation: permutation(T;L1;L2),  filter: filter(P;l),  list: T List,  assert: ↑b,  bool: 𝔹,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  implies: P ⇒ Q,  set: {x:A| B[x]} ,  apply: f a,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  member: t ∈ T,  so_lambda: λ2x.t[x],  implies: P ⇒ Q,  prop: ℙ,  so_apply: x[s],  top: Top,  or: P ∨ Q,  cons: [a / b],  uimplies: b supposing a,  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  uiff: uiff(P;Q),  and: P ∧ Q,  ifthenelse: if b then t else f fi ,  ge: i ≥ j ,  le: A ≤ B,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  not: ¬A,  bfalse: ff,  sq_type: SQType(T),  guard: {T},  bnot: ¬bb,  assert: ↑b,  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  cand: A c∧ B
Lemmas referenced :  list_induction,  all_wf,  list_wf,  permutation_wf,  bool_wf,  assert_wf,  filter_type,  filter_nil_lemma,  nil_wf,  filter_cons_lemma,  cons_wf,  list-cases,  product_subtype_list,  permutation_weakening,  permutation-length,  length_of_nil_lemma,  length_of_cons_lemma,  eqtt_to_assert,  non_neg_length,  satisfiable-full-omega-tt,  intformand_wf,  intformle_wf,  itermConstant_wf,  itermVar_wf,  intformeq_wf,  itermAdd_wf,  int_formula_prop_and_lemma,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_term_value_var_lemma,  int_formula_prop_eq_lemma,  int_term_value_add_lemma,  int_formula_prop_wf,  eqff_to_assert,  equal_wf,  bool_cases_sqequal,  subtype_base_sq,  bool_subtype_base,  assert-bnot,  permutation-cons,  filter_append_sq,  append_wf,  length_wf,  length-append,  exists_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  cut,  thin,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  hypothesisEquality,  sqequalRule,  lambdaEquality,  cumulativity,  hypothesis,  functionEquality,  setEquality,  applyEquality,  functionExtensionality,  independent_functionElimination,  dependent_functionElimination,  isect_memberEquality,  voidElimination,  voidEquality,  because_Cache,  rename,  universeEquality,  unionElimination,  promote_hyp,  hypothesis_subsumption,  productElimination,  independent_isectElimination,  equalityElimination,  equalityTransitivity,  equalitySymmetry,  natural_numberEquality,  dependent_pairFormation,  int_eqEquality,  intEquality,  independent_pairFormation,  computeAll,  instantiate,  hyp_replacement,  applyLambdaEquality,  dependent_set_memberEquality,  productEquality

Latex:
\mforall{}[A:Type]
    \mforall{}L1,L2:A  List.
        (permutation(A;L1;L2)  {}\mRightarrow{}  (\mforall{}p:A  {}\mrightarrow{}  \mBbbB{}.  permutation(\{a:A|  \muparrow{}(p  a)\}  ;filter(p;L1);filter(p;L2))))



Date html generated: 2017_04_17-AM-08_24_46
Last ObjectModification: 2017_02_27-PM-04_46_50

Theory : list_1


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