∀ {α : Type u_1} [inst : AddCommGroup α] [inst_1 : LinearOrder α] [inst_2 : IsOrderedAddMonoid α] [hα : Archimedean α]
  {p p_1 : α} (e_p : p = p_1) (hp : 0 < p) (a a_1 : α),
  a = a_1 → ∀ (b b_1 : α), b = b_1 → toIcoDiv hp a b = toIcoDiv ⋯ a_1 b_1