OAI/Combinatorics/ProgressionColoring/LongPeriodRegularGrid.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

The regular-position bound instantiated with the actual shifted rational grids and their actual integer periods.

  1. theorem OAI.QuantitativeVanDerWaerden.long_block_regular_card line 14

    Source documentation

    At least half the positions in a full long-period block are regular. The coordinate count is proved by the rational-grid theorem, including grid multiplicity; it is not an assumption of this statement.

    theorem long_block_regular_card {D h : ℕ} (hh : 0 < h) (hD : 0 < D)
        (rotating : Finset (Fin D)) (Y : Fin h → Fin D → ℝ)
        (y v : Fin D → ℝ) (a : Fin D → ℕ) (η : ℝ) (hη : 0 ≤ η)
        (hpath : ∀ i ∈ rotating, ∀ z, ∃ e : ℤ,
          Y z i - y i - (z.val : ℝ) / h * ((a i : ℝ) + v i) = e)
        (hdrift : ∀ i ∈ rotating, |v i| < η)
        (hperiod : ∀ i ∈ rotating, D ^ 2 < h / Nat.gcd h (a i))
        (hsmall : (D : ℝ) * (4 * η + 1 / (D : ℝ) ^ 2) ≤ 1 / 2) :
        (h : ℝ) / 2 ≤
          ((Finset.univ.filter fun z => ∀ i ∈ rotating, η ≤ rho (Y z i)).card : ℝ) := by
    …

    Mentions: OAI.QuantitativeVanDerWaerden.rho

  2. theorem OAI.QuantitativeVanDerWaerden.long_block_regular_card_at_scale line 53