OAI/NumberTheory/Ostmann/Construction/GoodCellSelection.lean
4 declarations, 0 contain sorry, 0 declared as axioms
Selecting many heavy cells with positive mean
- def
OAI.Ostmann.positiveHeavyCellsline 12 - theorem
OAI.Ostmann.positiveHeavyCells_massline 17Source documentation
Removing low-mass cells from a positively biased shell retains a fixed amount of mass.
theorem positiveHeavyCells_mass (I : Finset ℕ) (w score : ℕ → ℝ) (δ θ : ℝ) (hw : ∀ h ∈ I, 0 ≤ w h) (hδ : 0 ≤ δ) (hθ : 0 ≤ θ) (hscore : ∀ h ∈ I, score h ≤ 1) (hbias : δ * (∑ h ∈ I, w h) ≤ ∑ h ∈ I, w h * score h) (hthin : I.card * θ ≤ (δ / 4) * ∑ h ∈ I, w h) : (δ / 4) * (∑ h ∈ I, w h) ≤ ∑ h ∈ positiveHeavyCells I w score δ θ, w h := by …Mentions: OAI.Ostmann.positiveHeavyCells
- theorem
OAI.Ostmann.positiveHeavyCells_cardline 47Source documentation
A cellwise upper mass bound converts retained mass into a lower bound on the number of usable cell indices.
theorem positiveHeavyCells_card (I : Finset ℕ) (w score : ℕ → ℝ) (δ θ M : ℝ) (hw : ∀ h ∈ I, 0 ≤ w h) (hδ : 0 ≤ δ) (hθ : 0 ≤ θ) (hscore : ∀ h ∈ I, score h ≤ 1) (hbias : δ * (∑ h ∈ I, w h) ≤ ∑ h ∈ I, w h * score h) (hthin : I.card * θ ≤ (δ / 4) * ∑ h ∈ I, w h) (hcap : ∀ h ∈ I, w h ≤ M) : (δ / 4) * (∑ h ∈ I, w h) ≤ (positiveHeavyCells I w score δ θ).card * M := by …Mentions: OAI.Ostmann.positiveHeavyCells
- theorem
OAI.Ostmann.dense_index_targetline 65Source documentation
An arbitrary dense set of cell indices has the required target words; its minimum and maximum need not be chosen in advance.
theorem dense_index_target (δ : ℝ) (hδ : 0 < δ) : ∃ C : ℝ, 0 < C ∧ ∀ (I : Finset ℕ) (B : ℕ), (∀ x ∈ I, x ≤ B) → δ * B + 2 ≤ I.card → ∀ T : ℝ, C * B ≤ T → ∃ (n : ℕ) (w : List ℕ), w.length = n ∧ (∀ x ∈ w, x ∈ I) ∧ |(w.sum : ℝ) - T| < δ⁻¹ ∧ (n : ℝ) * B ≤ 2 * T / δ ∧ T < (n + 1 : ℕ) * B := by …