Vectorizing second derivative expression for Lagrange polynomials

Hi everyone,

I am trying to vectorize the following expression for the second derivative of the jth Lagrange polynomial at the ith construction point.

I have been able to vectorize the expression for the innermost product, but I am running into issues when trying to vectorize the outer sums.

I would greatly appreciate any help in vectorizing this expression:

[Julio Dutra]

Have you got any answer? I would appreciate if could share it. Thank you for your time.