OAI/RingTheory/DirectFiniteness/RibbonRestriction.lean

GitHub source file

13 declarations, 0 contain sorry, 0 declared as axioms

  1. def OAI.KaplanskyCounterexample.Planar.restrictQuotient line 15
  2. lemma OAI.KaplanskyCounterexample.Planar.restrictQuotient_injective line 19
  3. def OAI.KaplanskyCounterexample.Planar.quotientRestrictSumEquiv line 32

    Source documentation

    Components of an invariant subset and of its complement partition the components of the original finite set.

    def quotientRestrictSumEquiv (s : Setoid α) (P : α → Prop)
        (hP : ∀ {x y}, s.r x y → (P x ↔ P y)) :
        (Quotient (s.comap (Subtype.val : {x // P x} → α)) ⊕
          Quotient (s.comap (Subtype.val : {x // ¬ P x} → α))) ≃ Quotient s :=
    …
  4. lemma OAI.KaplanskyCounterexample.Planar.quotient_restrict_card_split line 59
  5. lemma OAI.KaplanskyCounterexample.Planar.perm_invariant_cycle line 68
  6. lemma OAI.KaplanskyCounterexample.Planar.subtype_cycles_setoid line 74
  7. lemma OAI.KaplanskyCounterexample.Planar.cycles_restrict_card_split line 80
  8. def OAI.KaplanskyCounterexample.Planar.Ribbon.restrict line 88

    Source documentation

    Restrict a ribbon to a union of its connected components.

    def Ribbon.restrict (R : Ribbon α) (P : α → Prop)
        (hb : ∀ x, P (R.black x) ↔ P x) (hw : ∀ x, P (R.white x) ↔ P x) :
        Ribbon {x // P x} where
    …

    Mentions: OAI.KaplanskyCounterexample.Planar.Ribbon

  9. lemma OAI.KaplanskyCounterexample.Planar.Ribbon.restrict_face line 95
  10. lemma OAI.KaplanskyCounterexample.Planar.Ribbon.invariant_components line 98
  11. lemma OAI.KaplanskyCounterexample.Planar.Ribbon.restrict_components line 107
  12. def OAI.KaplanskyCounterexample.Planar.Ribbon.GenusZero line 143

    Source documentation

    Euler equality componentwise, i.e., genus zero for all components.

    def Ribbon.GenusZero (R : Ribbon α) : Prop :=
    …

    Mentions: OAI.KaplanskyCounterexample.Planar.Ribbon

  13. lemma OAI.KaplanskyCounterexample.Planar.Ribbon.planar_restrict line 147