18.4 Graphics18.6 Symmetry, Special Values, and Limits to Monomials

§18.5 Explicit Representations

Contents

§18.5(i) Trigonometric Functions

§18.5(ii) Rodrigues Formulas

18.5.5p_{n}(x)=\frac{1}{\kappa _{n}w(x)}\frac{{d}^{n}}{{dx}^{n}}\left(w(x)(F(x))^{n}\right).

In this equation w(x) is as in Table 18.3.1, and F(x), \kappa _{n} are as in Table 18.5.1.

§18.5(iii) Finite Power Series, the Hypergeometric Function, and Generalized Hypergeometric Functions

For the definitions of \mathop{{{}_{{2}}F_{{1}}}\/}\nolimits, \mathop{{{}_{{1}}F_{{1}}}\/}\nolimits, and \mathop{{{}_{{2}}F_{{0}}}\/}\nolimits see §16.2.

Hermite

For corresponding formulas for Chebyshev, Legendre, and the Hermite \mathop{\mathit{He}_{{n}}\/}\nolimits polynomials apply (18.7.3)–(18.7.6), (18.7.9), and (18.7.11).

Note. The first of each of equations (18.5.7) and (18.5.8) can be regarded as definitions of \mathop{P^{{(\alpha,\beta)}}_{{n}}\/}\nolimits\!\left(x\right) when the conditions \alpha>-1 and \beta>-1 are not satisfied. However, in these circumstances the orthogonality property (18.2.1) disappears. For this reason, and also in the interest of simplicity, in the case of the Jacobi polynomials \mathop{P^{{(\alpha,\beta)}}_{{n}}\/}\nolimits\!\left(x\right) we assume throughout this chapter that \alpha>-1 and \beta>-1, unless stated otherwise. Similarly in the cases of the ultraspherical polynomials \mathop{C^{{(\lambda)}}_{{n}}\/}\nolimits\!\left(x\right) and the Laguerre polynomials \mathop{L^{{(\alpha)}}_{{n}}\/}\nolimits\!\left(x\right) we assume that \lambda>-\tfrac{1}{2},\lambda\neq 0, and \alpha>-1, unless stated otherwise.

§18.5(iv) Numerical Coefficients

Legendre

Hermite

18.5.18
\mathop{H_{{0}}\/}\nolimits\!\left(x\right)=1,
\mathop{H_{{1}}\/}\nolimits\!\left(x\right)=2x,
\mathop{H_{{2}}\/}\nolimits\!\left(x\right)=4x^{2}-2,
\mathop{H_{{3}}\/}\nolimits\!\left(x\right)=8x^{3}-12x,
\mathop{H_{{4}}\/}\nolimits\!\left(x\right)=16x^{4}-48x^{2}+12,
\mathop{H_{{5}}\/}\nolimits\!\left(x\right)=32x^{5}-160x^{3}+120x,
\mathop{H_{{6}}\/}\nolimits\!\left(x\right)=64x^{6}-480x^{4}+720x^{2}-120.
18.5.19
\mathop{\mathit{He}_{{0}}\/}\nolimits\!\left(x\right)=1,
\mathop{\mathit{He}_{{1}}\/}\nolimits\!\left(x\right)=x,
\mathop{\mathit{He}_{{2}}\/}\nolimits\!\left(x\right)=x^{2}-1,
\mathop{\mathit{He}_{{3}}\/}\nolimits\!\left(x\right)=x^{3}-3x,
\mathop{\mathit{He}_{{4}}\/}\nolimits\!\left(x\right)=x^{4}-6x^{2}+3,
\mathop{\mathit{He}_{{5}}\/}\nolimits\!\left(x\right)=x^{5}-10x^{3}+15x,
\mathop{\mathit{He}_{{6}}\/}\nolimits\!\left(x\right)=x^{6}-15x^{4}+45x^{2}-15.

For the corresponding polynomials of degrees 7 through 12 see Abramowitz and Stegun (1964, Tables 22.3, 22.5, 22.9, 22.10, 22.12).