English
A recurrence formula for torusIntegral with successor operation.
Русский
Рекуррентная формула для torusIntegral с операцией successor.
LaTeX
$$$\operatorname{torusIntegral}(f,c,R) = \operatorname{circleIntegral}(\cdot, c_0, R_0)$$$$
Lean4
/-- Recurrent formula for `torusIntegral`, see also `torusIntegral_succAbove`. -/
theorem torusIntegral_succ {f : (ℂⁿ ⁺ ¹) → E} {c : ℂⁿ ⁺ ¹} {R : ℝⁿ ⁺ ¹} (hf : TorusIntegrable f c R) :
(∯ x in T(c, R), f x) = ∮ x in C(c 0, R 0), ∯ y in T(c ∘ Fin.succ, R ∘ Fin.succ), f (Fin.cons x y) := by
simpa using torusIntegral_succAbove hf 0