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 Heckman and Opdam (1987). They generalize Jack polynomials when the root 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
Heckman, G. J.; Opdam, E. M. (1987), "Root systems and hypergeometric functions. I", Compositio Mathematica, 64 (3): 329–352, MR 0918416 Heckman, G. J.; Opdam, E. M. (1987b), "Root systems and hypergeometric functions. II", Compositio Mathematica, 64 (3): 353–373, MR 0918417 Opdam, E. M. (1988), "Root systems and hypergeometric functions. III", Compositio Mathematica, 67 (1): 21–49, MR 0949270 Opdam, E. M. (1988b), "Root systems and hypergeometric functions. IV", Compositio Mathematica, 67 (2): 191–209., MR 0951750
