lean_workbook_plus_49368

Proved

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

Find the closed form of the sequence defined by $a_0=1;a_1=6; a_{n+2}=6a_{n+1}-a_n$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_49368 (a : ℕ → ℕ) (a0 : a 0 = 1) (a1 : a 1 = 6) (a_rec : ∀ n, a (n + 2) = 6 * a (n + 1) - a n) : ∃ f : ℕ → ℕ, ∀ n, a n = f n   :=  by sorry

Source

https://huggingface.co/datasets/internlm/Lean-Workbook

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