English
Under locally uniform convergence on a ct thickening, derivative convergence holds uniformly on K.
Русский
При локальной равномерной сходимости на ct-уплотнении производная сходится равномерно на K.
LaTeX
$$$TendstoUniformlyOn (Function.comp deriv F) (Complex.cderiv δ f) φ K$ under the stated hypotheses$$
Lean4
theorem exists_cthickening_tendstoUniformlyOn (hf : TendstoLocallyUniformlyOn F f φ U)
(hF : ∀ᶠ n in φ, DifferentiableOn ℂ (F n) U) (hK : IsCompact K) (hU : IsOpen U) (hKU : K ⊆ U) :
∃ δ > 0, cthickening δ K ⊆ U ∧ TendstoUniformlyOn (deriv ∘ F) (cderiv δ f) φ K :=
by
obtain ⟨δ, hδ, hKδ⟩ := hK.exists_cthickening_subset_open hU hKU
exact ⟨δ, hδ, hKδ, tendstoUniformlyOn_deriv_of_cthickening_subset hf hF hδ hK hU hKδ⟩