English
For any x and n, evaluating the VerschiebungPoly(n) under the coefficient algebra of x yields the n-th coefficient of verschiebungFun x.
Русский
Для любого x и n, применение aeval к verschiebungPoly(n) по коэффициентам x дает n-й коэффициент verschiebungFun x.
LaTeX
$$$$ \\mathrm{aeval}(x.\\\\coeff, \\\\mathrm{verschiebungPoly}(n)) = (\\\\text{verschiebungFun}(x)).coeff(n). $$$$
Lean4
theorem aeval_verschiebung_poly' (x : 𝕎 R) (n : ℕ) : aeval x.coeff (verschiebungPoly n) = (verschiebungFun x).coeff n :=
by
rcases n with - | n
· simp only [verschiebungPoly, ite_true, map_zero, verschiebungFun_coeff_zero]
· rw [verschiebungPoly, verschiebungFun_coeff_succ, if_neg n.succ_ne_zero, aeval_X, add_tsub_cancel_right]