Let f be an infinitely differentiable real-valued function on a bounded interval I. Take n ≥ 1 interpolation points {x₀, x₁, ....., x_n-1}. Take n additional interpolation points

x_n+j = x_j + ε, j = 0, 1, ....., n - 1

where ε > 0 is such that {x0, x1, ....., x₂n-1} are all distinct.

Let p_2n-1 be the Lagrange interpolation polynomial of degree 2n - 1 with the interpolation points {x0, x1, ....., x2n-1} for the function f.

Let q2n-1 be the Hermite interpolation polynomial of degree 2n - 1 with the interpolation points {x0, x1, ....., xn-1} for the function f. In the ε → 0 limit, the quantity