English
The set of n-smooth numbers equals the factoredNumbers of primes below n.
Русский
Множество n-гладких чисел равно факторированию по(primesBelow n).
LaTeX
$$$\mathrm{smoothNumbers}(n) = \mathrm{factoredNumbers}(n\.primesBelow)$$$
Lean4
/-- The `n`-smooth numbers agree with the `primesBelow n`-factored numbers. -/
theorem smoothNumbers_eq_factoredNumbers_primesBelow (n : ℕ) : smoothNumbers n = factoredNumbers n.primesBelow :=
by
rw [smoothNumbers_eq_factoredNumbers]
refine Set.Subset.antisymm (fun m hm ↦ ?_) <| factoredNumbers_mono Finset.mem_of_mem_filter
simp_rw [mem_factoredNumbers'] at hm ⊢
exact fun p hp hp' ↦ mem_primesBelow.mpr ⟨Finset.mem_range.mp <| hm p hp hp', hp⟩