OAI/Algebra/DepthFive/SmallDegreeCorrections.lean

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3 declarations, 0 contain sorry, 0 declared as axioms

  1. theorem OAI.Problem335.rpow_one_sub_le_chord line 13

    Source documentation

    A convex chord controls the small-degree correction, without differentiating its logarithm.

    theorem rpow_one_sub_le_chord (q z : ℝ) (hq : 0 < q)
        (hz : 0 ≤ z) (hz' : z ≤ 1 / 4) :
        q ^ (1 - z) ≤ q + 4 * z * q ^ ((3 : ℝ) / 4) := by
    …
  2. theorem OAI.Problem335.sum_rpow_one_sub_le_chord line 28

    Source documentation

    Sum version of the chord estimate.

    theorem sum_rpow_one_sub_le_chord {ι : Type*} (I : Finset ι)
        (q : ℝ) (z : ι → ℝ) (hq : 0 < q)
        (hz : ∀ i ∈ I, 0 ≤ z i) (hz' : ∀ i ∈ I, z i ≤ 1 / 4) :
        ∑ i ∈ I, q ^ (1 - z i) ≤
          (I.card : ℝ) * q + 4 * (∑ i ∈ I, z i) * q ^ ((3 : ℝ) / 4) := by
    …
  3. theorem OAI.Problem335.sum_small_degree_corrections_le line 43

    Source documentation

    The total low-degree correction is O(sqrt n), uniformly in the number and sizes of factors. The degree variables may be real; natural degrees are a special case.

    theorem sum_small_degree_corrections_le {ι : Type*} (I : Finset ι)
        (n s q : ℝ) (e : ι → ℝ)
        (hn : 0 < n) (hs : 0 ≤ s) (hs' : s ≤ Real.sqrt n)
        (hq : 0 < q) (hqone : q ≤ 1) (hqsmall : q ≤ 2 / Real.sqrt n)
        (he : ∀ i ∈ I, 1 ≤ e i)
        (helow : ∀ i ∈ I, s * e i / n ≤ 1 / 4)
        (hesum : ∑ i ∈ I, e i ≤ n) :
        ∑ i ∈ I, q ^ (1 - s * e i / n) ≤ 6 * Real.sqrt n := by
    …