Nuprl Lemma : count-as-filter

∀[T:Type]. ∀[P:T ⟶ 𝔹]. ∀[L:T List].  (count(P;L) ~ ||filter(P;L)||)


Proof




Definitions occuring in Statement :  count: count(P;L),  length: ||as||,  filter: filter(P;l),  list: T List,  bool: 𝔹,  uall: ∀[x:A]. B[x],  function: x:A ⟶ B[x],  universe: Type,  sqequal: s ~ t
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  all: ∀x:A. B[x],  nat: ℕ,  implies: P ⇒ Q,  false: False,  ge: i ≥ j ,  uimplies: b supposing a,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  not: ¬A,  top: Top,  and: P ∧ Q,  prop: ℙ,  subtype_rel: A ⊆r B,  guard: {T},  or: P ∨ Q,  filter: filter(P;l),  count: count(P;L),  cons: [a / b],  colength: colength(L),  so_lambda: λ2x y.t[x; y],  so_apply: x[s1;s2],  decidable: Dec(P),  nil: [],  it: ⋅,  so_lambda: λ2x.t[x],  so_apply: x[s],  sq_type: SQType(T),  less_than: a < b,  squash: ↓T,  less_than': less_than'(a;b),  bool: 𝔹,  unit: Unit,  btrue: tt,  uiff: uiff(P;Q),  ifthenelse: if b then t else f fi ,  bfalse: ff,  bnot: ¬bb,  assert: ↑b
Lemmas referenced :  nat_properties,  satisfiable-full-omega-tt,  intformand_wf,  intformle_wf,  itermConstant_wf,  itermVar_wf,  intformless_wf,  int_formula_prop_and_lemma,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_term_value_var_lemma,  int_formula_prop_less_lemma,  int_formula_prop_wf,  ge_wf,  less_than_wf,  equal-wf-T-base,  nat_wf,  colength_wf_list,  less_than_transitivity1,  less_than_irreflexivity,  list-cases,  reduce_nil_lemma,  length_of_nil_lemma,  product_subtype_list,  spread_cons_lemma,  intformeq_wf,  itermAdd_wf,  int_formula_prop_eq_lemma,  int_term_value_add_lemma,  decidable__le,  intformnot_wf,  int_formula_prop_not_lemma,  le_wf,  equal_wf,  subtract_wf,  itermSubtract_wf,  int_term_value_subtract_lemma,  subtype_base_sq,  set_subtype_base,  int_subtype_base,  decidable__equal_int,  reduce_cons_lemma,  bool_wf,  eqtt_to_assert,  length_of_cons_lemma,  add-commutes,  eqff_to_assert,  bool_cases_sqequal,  bool_subtype_base,  assert-bnot,  zero-add,  length_wf,  filter_wf5,  subtype_rel_dep_function,  l_member_wf,  subtype_rel_self,  set_wf,  list_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  thin,  lambdaFormation,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  hypothesisEquality,  hypothesis,  setElimination,  rename,  intWeakElimination,  natural_numberEquality,  independent_isectElimination,  dependent_pairFormation,  lambdaEquality,  int_eqEquality,  intEquality,  dependent_functionElimination,  isect_memberEquality,  voidElimination,  voidEquality,  sqequalRule,  independent_pairFormation,  computeAll,  independent_functionElimination,  sqequalAxiom,  cumulativity,  applyEquality,  because_Cache,  unionElimination,  promote_hyp,  hypothesis_subsumption,  productElimination,  equalityTransitivity,  equalitySymmetry,  applyLambdaEquality,  dependent_set_memberEquality,  addEquality,  baseClosed,  instantiate,  imageElimination,  functionExtensionality,  equalityElimination,  setEquality,  functionEquality,  universeEquality

Latex:
\mforall{}[T:Type].  \mforall{}[P:T  {}\mrightarrow{}  \mBbbB{}].  \mforall{}[L:T  List].    (count(P;L)  \msim{}  ||filter(P;L)||)



Date html generated: 2018_05_21-PM-06_37_27
Last ObjectModification: 2017_07_26-PM-04_53_00

Theory : general


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