lean_workbook_plus_78822

Disproved

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

Given $f: Z\rightarrow R$ which satisfies $f(n) = n-3$ if $n\ge 1000$ and $f(n) = f(f(n+5))$ if $n <1000$ . Find the value of $f(94)$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_78822 (f : ℤ → ℝ) (hf : ∀ n, 1000 ≤ n → f n = n - 3) (hg : ∀ n, n < 1000 → f n = f (n + 5)) : f 94 = 91   :=  by sorry

Source