theorem lean_workbook_plus_14201 (f : ℝ → ℝ) (a b c : ℝ) (ha : 0 < a) (hb : 0 < b) (hc : 0 < c) : (f a + f b) / 2 + (f b + f c) / 2 + (f c + f a) / 2 ≥ f (a + b) / 2 + f (b + c) / 2 + f (c + a) / 2 → 1 / a + 1 / b + 1 / c ≥ 2 / (a + b) + 2 / (b + c) + 2 / (c + a) := by sorry