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Explicit Formulas for the Associated Jacobi Polynomials and Some Applications

Published online by Cambridge University Press:  20 November 2018

Jet Wimp*
Affiliation:
Drexel University, Philadelphia, Pennsylvania
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In this paper we determine closed-form expressions for the associated Jacobi polynomials, i.e., the polynomials satisfying the recurrence relation for Jacobi polynomials with n replaced by n + c, for arbitrary real c ≧ 0. One expression allows us to give in closed form the [n — 1/n] Padé approximant for what is essentially Gauss' continued fraction, thus completing the theory of explicit representations of main diagonal and off-diagonal Padé approximants to the ratio of two Gaussian hypergeometric functions and their confluent forms, an effort begun in [2] and [19]. (We actually give only the [n — 1/n] Padé element, although other cases are easily constructed, see [19] for details.)

We also determine the weight function for the polynomials in certain cases where there are no discrete point masses. Concerning a weight function for these polynomials, so many writers have obtained so many partial results that our formula should be considered an epitome rather than a real discovery, see the discussion in Section 3.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1987

References

1. Askey, R. and Ismail, M., Recurrence relations, continued fractions and orthogonal polynomials, Memoirs Amer. Math. Soc. 300 (Providence, RI, 1984).Google Scholar
2. Askey, R. and Wimp, J., Associated Laguerre polynomials, Proc. Roy. Soc. Edinburgh 96 (1984), 1537.Google Scholar
3. Bailey, W. N., Generalized hyper geometric series (Cambridge University Press, Cambridge, 1935).Google Scholar
4. Barrucand, P. and Dickinson, D., On the associated Legendre polynomials in Orthogonal expansions and their continuous analogs (Southern Illinois University Press, Carbondale, IL, 1967).Google Scholar
5. Fo, J. Bellandi and de Oliveira, E. C., On the product of two Jacobi functions of different kinds with different arguments, J. Phys. 15 (1982).Google Scholar
6. Bustoz, J. and Ismail, M., The associated ultraspherical polynomials and their q-analogues, Can. J. Math. 34 (1982), 718736.Google Scholar
7. Cohen, M. E., On J acobi functions and multiplication theorems for intergrals of Bessel functions, J. Math. Anal. Appl. 57 (1977), 469475.Google Scholar
8. Erdélyi, A. et al, Higher transcendental functions, 3v. (McGraw-Hill, NY, 1953).Google Scholar
9. Flensted-Jensen, M. and Koornwinder, T., The convolution structure for Jacobi function expansions, Ark. Mat. 11 (1975), 245262.Google Scholar
10. Luke, Y. L., Mathematical functions and their approximations (Acad. Press, NY, 1975).Google Scholar
11. Luke, Y. L., The special functions and their approximation, 2v. (Acad. Press, NY. 1969).Google Scholar
12. Nevai, P., A new class of orthogonal polynomials, Proc. Amer. Math. Soc. 91 (1984), 409415.Google Scholar
13. Pollaczek, F., Sur une famille de polynômes orthogonaux à quatre paramètres, C.R. Acad. Sci., Paris 230 (1950), 22542256.Google Scholar
14. Rainville, E. D., Special functions (MacMillan, NY, 1960).Google Scholar
15. Sherman, J., On the numerators of the convergents of the Stieltjes continued fraction, Trans. Amer. Math. Soc. 35 (1933), 6487.Google Scholar
16. Wall, H. S., Analytic theory of continued fractions (Chelsea, NY, 1948).Google Scholar
17. Watson, G. N., A treatise on the theory of Bessel functions (Cambridge University Press, Cambridge, 1962).Google Scholar
18. Wimp, J., Computation with recurrence relations (Pitman Press, London, 1984).Google Scholar
19. Wimp, J., Some explicit Padé approximants for the function Φ′/Φ and a related quadrature formula involving Bessel functions, SIAM J. Math. Anal. 76 (1985), 887895.Google Scholar