OAI/NumberTheory/EgyptianFractions/PrescribedAnalysis.lean

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5 declarations, 0 contain sorry, 0 declared as axioms

  1. theorem OAI.Problem337.slope_lower_of_double_exp line 11

    Source documentation

    Taking two logarithms converts a double exponential lower bound to a slope bound.

    theorem slope_lower_of_double_exp {x c : ℝ} {k : ℕ}
        (hk : 0 < k) (h : Real.exp (Real.exp (c * (k : ℝ))) ≤ x) :
        c ≤ Real.log (Real.log x) / (k : ℝ) := by
    …
  2. theorem OAI.Problem337.eventually_slope_lower_of_double_exp line 21

    Source documentation

    Eventual double exponential bounds lead to eventual lower bounds for the slope.

    theorem eventually_slope_lower_of_double_exp (f : ℕ → ℝ) (c : ℝ)
        (h : ∀ᶠ k : ℕ in atTop, Real.exp (Real.exp (c * (k : ℝ))) ≤ f k) :
        ∀ᶠ k : ℕ in atTop, c ≤ Real.log (Real.log (f k)) / (k : ℝ) := by
    …
  3. theorem OAI.Problem337.liminf_slope_lower_of_double_exp line 29

    Source documentation

    The lower limiting slope uses only eventual double exponential lower bounds and boundedness above; no Egyptian fraction constructions enter this step.

    theorem liminf_slope_lower_of_double_exp (f : ℕ → ℝ) (A : ℝ)
        (hupper : IsBoundedUnder (· ≤ ·) atTop
          (fun k : ℕ => Real.log (Real.log (f k)) / (k : ℝ)))
        (hlower : ∀ c : ℝ, c < A →
          ∀ᶠ k : ℕ in atTop, Real.exp (Real.exp (c * (k : ℝ))) ≤ f k) :
        A ≤ liminf (fun k : ℕ => Real.log (Real.log (f k)) / (k : ℝ)) atTop ∧
        liminf (fun k : ℕ => Real.log (Real.log (f k)) / (k : ℝ)) atTop ≤
          limsup (fun k : ℕ => Real.log (Real.log (f k)) / (k : ℝ)) atTop := by
    …
  4. theorem OAI.Problem337.one_div_six_hundred_lt_prescribed_rate line 48

    Source documentation

    A coarse elementary bound for log 2 is enough for the stated constant 600.

    theorem one_div_six_hundred_lt_prescribed_rate :
        (1 : ℝ) / 600 < Real.log 2 / 257 := by
    …
  5. theorem OAI.Problem337.eventually_double_exp_six_hundred line 55

    Source documentation

    Specialization of the family of rates to the explicit constant in the corollary.

    theorem eventually_double_exp_six_hundred (f : ℕ → ℝ)
        (h : ∀ c : ℝ, c < Real.log 2 / 257 →
          ∀ᶠ k : ℕ in atTop, Real.exp (Real.exp (c * (k : ℝ))) ≤ f k) :
        ∀ᶠ k : ℕ in atTop, Real.exp (Real.exp ((k : ℝ) / 600)) ≤ f k := by
    …