lean_workbook_plus_13042

Proved

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

Prove that if $x$ and $y$ are integers such that $x \equiv 1 \mod 3$ and $y \equiv 2 \mod 3$ , then $3 \nmid xy$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_13042 : ∀ x y : ℤ, x ≡ 1 [ZMOD 3] ∧ y ≡ 2 [ZMOD 3] → ¬ 3 ∣ (x * y)   :=  by sorry

Source