Computes the value of a (physicists') Hermite polynomial.
The value Hn(x).
Hermite polynomials are orthogonal on the interval (-∞,+∞) with the weight e-x2.

They appear in the solution of the one-dimensional, quantum mehanical, harmonic oscilator.
Statisticans' Hermite polynomials (see HermiteHe(Int32, Double)) are related to physicists' Hermite polynomials via Hn(x) = 2nHn(x √2). Staticians' Hermite polynomials do not grow as quickly as physicists', and may therefore be preferable for large values of n and x which could overflow Double.