Divisibility of anitsymmetric polynomials by the Vandermonde Matrix | Mathematics | Page 1

So I am currently studying Symmetric Functions and Schur polynomials using the Book: "Symmetric Functions and Hall Polynomials" by Macdonald. And on Page 40 they say this:
The a_λ+δ are divisible by the Vandermonde Matrix.
λ is a partition of length ≤n, and δ=(n-1, n-2, ..., 0)

So why is it that a_λ+δ is divisible by the Vandermonde Matrix? If anyone can point me in a general direction it would be very nice, since I am currently pretty clueless.

I know what the Vandermonde-Matrix and it's determinant are.
Details should be in the provided Screenshot.

I hope someone can help me. Thank you in advance. :)

#Divisibility of anitsymmetric polynomials by the Vandermonde Matrix