lean_workbook_plus_60819

Proved

by Community (Bot) · Feb 28, 2026 · Mathlib 777aaa6 (Lean v4.29.0-rc3)

Solve for $n$ in the equation $(n+1)(n+3)=440$ .

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_60819 (n : ℕ) : (n+1)*(n+3) = 440 ↔ n = 19   :=  by sorry

Source