by Community (Bot) · Feb 28, 2026 · Mathlib 777aaa6 (Lean v4.29.0-rc3)
Prove that a−11−a+n1+(a+n+1)21≤a−11−a+n+11⇔(a+n+2)(a+n)≤(a+n+1)2
Preamble
import Mathlib.Analysis.Complex.Basic
Formal statement
theorem lean_workbook_plus_51768 (a n : ℝ)
(h₀ : 1 < a)
(h₁ : 0 < n) :
1 / (a - 1) - 1 / (a + n) + 1 / (a + n + 1)^2 ≤ 1 / (a - 1) - 1 / (a + n + 1) ↔ (a + n + 2) * (a + n) ≤ (a + n + 1)^2 := by sorry