Nuprl Lemma : l_intersection-size

∀[T:Type]. ∀[eq:EqDecider(T)]. ∀[a,b,c:T List].
  (no_repeats(T;a) ⇒ no_repeats(T;b) ⇒ a ⊆ c ⇒ b ⊆ c ⇒ ((||a|| + ||b||) ≤ (||c|| + ||(a ⋂ b)||)))


Proof




Definitions occuring in Statement :  l_intersection: (L1 ⋂ L2),  l_contains: A ⊆ B,  no_repeats: no_repeats(T;l),  length: ||as||,  list: T List,  deq: EqDecider(T),  uall: ∀[x:A]. B[x],  le: A ≤ B,  implies: P ⇒ Q,  add: n + m,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  implies: P ⇒ Q,  l_intersection: (L1 ⋂ L2),  uimplies: b supposing a,  l_contains: A ⊆ B,  l_member: (x ∈ l),  l_all: (∀x∈L.P[x]),  exists: ∃x:A. B[x],  int_seg: {i..j-},  subtype_rel: A ⊆r B,  lelt: i ≤ j < k,  and: P ∧ Q,  ge: i ≥ j ,  guard: {T},  all: ∀x:A. B[x],  prop: ℙ,  decidable: Dec(P),  or: P ∨ Q,  false: False,  nat: ℕ,  not: ¬A,  satisfiable_int_formula: satisfiable_int_formula(fmla),  top: Top,  less_than: a < b,  squash: ↓T,  le: A ≤ B,  cand: A c∧ B,  pi1: fst(t),  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  uiff: uiff(P;Q),  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  ifthenelse: if b then t else f fi ,  bfalse: ff,  sq_type: SQType(T),  bnot: ¬bb,  assert: ↑b,  inject: Inj(A;B;f),  no_repeats: no_repeats(T;l),  less_than': less_than'(a;b),  so_lambda: λ2x.t[x],  so_apply: x[s],  true: True,  label: ...$L... t
Lemmas referenced :  no_repeats_filter,  non_neg_length,  int_seg_properties,  length_wf,  decidable__le,  lelt_wf,  length_wf_nat,  nat_properties,  full-omega-unsat,  istype-int,  int_formula_prop_and_lemma,  istype-void,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_term_value_var_lemma,  int_formula_prop_not_lemma,  int_seg_wf,  select_wf,  decidable__lt,  int_formula_prop_less_lemma,  no_repeats_l_index-inj,  l_intersection_wf,  l_contains_wf,  no_repeats_wf,  le_witness_for_triv,  list_wf,  deq_wf,  less_than_wf,  nat_wf,  member-intersection,  select_member,  l_index_wf,  l_member_wf,  pigeon-hole,  add_nat_wf,  add-is-int-iff,  int_term_value_add_lemma,  int_formula_prop_eq_lemma,  false_wf,  le_wf,  lt_int_wf,  eqtt_to_assert,  assert_of_lt_int,  eqff_to_assert,  bool_cases_sqequal,  subtype_base_sq,  bool_wf,  bool_subtype_base,  assert-bnot,  iff_weakening_uiff,  assert_wf,  subtract_wf,  intformand_wf,  intformnot_wf,  intformle_wf,  itermConstant_wf,  itermSubtract_wf,  itermVar_wf,  intformless_wf,  int_term_value_subtract_lemma,  int_formula_prop_wf,  itermAdd_wf,  deq-member_wf,  assert-deq-member,  add-member-int_seg1,  intformeq_wf,  decidable__equal_int_seg,  int_seg_subtype_nat,  set_subtype_base,  int_subtype_base,  equal_wf,  squash_wf,  true_wf,  subtype_rel_self,  iff_weakening_equal,  not_wf,  decidable__equal_int
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  Error :isect_memberFormation_alt,  introduction,  cut,  Error :lambdaFormation_alt,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  because_Cache,  independent_isectElimination,  hypothesis,  sqequalRule,  promote_hyp,  productElimination,  Error :dependent_pairFormation_alt,  hypothesisEquality,  Error :functionExtensionality_alt,  Error :dependent_set_memberEquality_alt,  applyEquality,  independent_pairFormation,  natural_numberEquality,  setElimination,  rename,  dependent_functionElimination,  Error :universeIsType,  unionElimination,  equalityTransitivity,  equalitySymmetry,  applyLambdaEquality,  independent_functionElimination,  voidElimination,  approximateComputation,  Error :lambdaEquality_alt,  int_eqEquality,  Error :isect_memberEquality_alt,  Error :functionIsType,  Error :equalityIsType1,  imageElimination,  functionExtensionality,  cumulativity,  Error :inhabitedIsType,  universeEquality,  Error :productIsType,  addEquality,  pointwiseFunctionality,  baseApply,  closedConclusion,  baseClosed,  equalityElimination,  instantiate,  hyp_replacement,  Error :equalityIsType4,  intEquality,  imageMemberEquality,  productEquality,  Error :equalityIsType3,  Error :equalityIsType2

Latex:
\mforall{}[T:Type].  \mforall{}[eq:EqDecider(T)].  \mforall{}[a,b,c:T  List].
    (no\_repeats(T;a)
    {}\mRightarrow{}  no\_repeats(T;b)
    {}\mRightarrow{}  a  \msubseteq{}  c
    {}\mRightarrow{}  b  \msubseteq{}  c
    {}\mRightarrow{}  ((||a||  +  ||b||)  \mleq{}  (||c||  +  ||(a  \mcap{}  b)||)))



Date html generated: 2019_06_20-PM-01_58_00
Last ObjectModification: 2018_10_03-PM-10_28_04

Theory : decidable!equality


Home Index