Heckman–Opdam polynomials
In mathematics, Heckman–Opdam polynomials (sometimes called Jacobi polynomials) Pλ(k) are orthogonal polynomials in several variables associated to root systems. They were introduced by . They generalize Jack polynomials  when the roots system is of type A, and are limits of Macdonald polynomials Pλ(q, t) as q tends to 1 and (1 − t)/(1 − q) tends to k.
Main properties of the Heckman–Opdam polynomials have been detailed by Siddhartha Sahi

References

Orthogonal polynomials