Validation, including an observation of independent interest: (i) a literal big-integer implementation (src/naive700.py, sharing no logic) is bit-identical on all composite n ≤ 800; (ii) OEIS A091963 — the minimum gcd of two interior Pascal-row entries, by definition a lower bound for f(n) since C(n,1)=n is interior — EQUALS f(n) on all 8,769 composite n ≤ 9999, i.e. the interior-pair minimum is always achieved against n itself in that range (zero bound violations, 100% equality).