rw [Iic_eq_cons_Iio, prod_cons]
α : Type u_1
β : Type u_2
inst✝² : PartialOrder α
inst✝¹ : CommMonoid β
f : α → β
a✝ b : α
inst✝ : LocallyFiniteOrderBot α
a : α
⊢ f a * ∏ x ∈ Iio a, f x = ∏ x ∈ Iic a, f x
no goals