have := centralBinomialUpper_monotone.le_of_tendsto centralBinomialUpper_limit n
n : ℕ
this : 0 < π
⊢ 4 ^ n / Real.sqrt (π * (↑n + 1 / 3)) ≤ ↑(centralBinom n)
n : ℕ
this✝ : 0 < π
this : (Real.sqrt π)⁻¹ ≤ centralBinomialUpper n
⊢ 4 ^ n / Real.sqrt (π * (↑n + 1 / 3)) ≤ ↑(centralBinom n)