lean_workbook_plus_52041

Proved

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

Prove that $\binom{n+2}{4}-\binom{n}{2}=2\binom{n}{3}+\binom{n}{4}$ .

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_52041 (n : ℕ) : (n + 2).choose 4 - n.choose 2 = 2 * n.choose 3 + n.choose 4   :=  by sorry

Source