OAI/Geometry/HyperbolicGroups/SeparatorDecomposition.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

  1. def OAI.HyperbolicObstruction.PlanarRecursion.HasBalancedSeparators line 17

    Source documentation

    Balanced vertex separators of size at most the square-root bound.

    def HasBalancedSeparators (G : SimpleGraph V) (c : ℝ) : Prop :=
    …
  2. theorem OAI.HyperbolicObstruction.PlanarRecursion.partition_of_balanced_separators line 26

    Source documentation

    Recursive charging for finite parts and removed vertices using balanced separators and a finite cutoff.

    theorem partition_of_balanced_separators {G : SimpleGraph V} {c : ℝ} (hc : 0 ≤ c)
        (hsep : HasBalancedSeparators G c) (K : ℕ) (hK : 0 < K)
        (hcap : 144*c^2 ≤ (K : ℝ)) (U : Finset V) :
        ∃ P : CutPartition G U K, (P.removed.card : ℝ) ≤ 16*c*U.card/Real.sqrt K := by
    …

    Mentions: OAI.HyperbolicObstruction.PlanarRecursion.HasBalancedSeparators, OAI.HyperbolicObstruction.PlanarRecursion.CutPartition