lean_workbook_plus_39062

Proved

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

Noting then that $7^4\equiv 1\pmod {10}$ , we get $7^{2003}\equiv 7^3\equiv 3\pmod {10}$ Hence the answer $\boxed{3}$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_39062 : 7 ^ 2003 ≡ 3 [MOD 10]   :=  by sorry

Source