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30 Spheroidal Wave FunctionsNotation

§30.1 Special Notation

(For other notation see Notation for the Special Functions.)

x real variable. Except in §§30.7(iv), 30.11(ii), 30.13, and 30.14, -1<x<1.
\gamma^{2} real parameter (positive, zero, or negative).
m order, a nonnegative integer.
n degree, an integer n=m,m+1,m+2,\dots.
k integer.
\delta arbitrary small positive constant.

The main functions treated in this chapter are the eigenvalues \lambda^{m}_{n}\left(\gamma^{2}\right) and the spheroidal wave functions \mathsf{Ps}^{m}_{n}\left(x,\gamma^{2}\right), \mathsf{Qs}^{m}_{n}\left(x,\gamma^{2}\right), \mathit{Ps}^{m}_{n}\left(z,\gamma^{2}\right), \mathit{Qs}^{m}_{n}\left(z,\gamma^{2}\right), and S^{m(j)}_{n}\left(z,\gamma\right), j=1,2,3,4. These notations are similar to those used in Arscott (1964b) and Erdélyi et al. (1955). Meixner and Schäfke (1954) use \mathrm{ps}, \mathrm{qs}, \mathrm{Ps}, \mathrm{Qs} for \mathsf{Ps}, \mathsf{Qs}, \mathit{Ps}, \mathit{Qs}, respectively.

Other Notations

Flammer (1957) and Abramowitz and Stegun (1964) use \lambda_{mn}(\gamma) for \lambda^{m}_{n}\left(\gamma^{2}\right)+\gamma^{2}, R_{mn}^{(j)}(\gamma,z) for S^{m(j)}_{n}\left(z,\gamma\right), and

where d_{mn}(\gamma) is a normalization constant determined by

30.1.2
S^{(1)}_{mn}(\gamma,0)=(-1)^{m}\mathsf{P}^{m}_{n}\left(0\right),n-m even,
\left.\frac{\mathrm{d}}{\mathrm{d}x}S^{(1)}_{mn}(\gamma,x)\right|_{x=0}=(-1)^{%
m}\left.\frac{\mathrm{d}}{\mathrm{d}x}\mathsf{P}^{m}_{n}\left(x\right)\right|_%
{x=0},n-m odd.

For older notations see Abramowitz and Stegun (1964, §21.11) and Flammer (1957, pp. 14,15).