English
If 0 < n and n is not prime, then minFac(n) ≤ n / minFac(n).
Русский
Если 0 < n и n не простое, то minFac(n) ≤ n / minFac(n).
LaTeX
$$$\\\\text{0} < n \\\\land \\\\neg \\\\mathrm{Prime}(n) \\\\Rightarrow \\\\minFac(n) \\\\le \\\\dfrac{n}{\\\\minFac(n)}.$$$
Lean4
theorem minFac_le_of_dvd {n : ℕ} : ∀ {m : ℕ}, 2 ≤ m → m ∣ n → minFac n ≤ m :=
by
by_cases n1 : n = 1
· exact fun m2 _ => n1.symm ▸ le_trans (by simp) m2
· apply (minFac_has_prop n1).2.2