9 Airy and Related Functions9.2 Differential Equation

§9.1 Special Notation

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

k nonnegative integer, except in §9.9(iii).
x real variable.
z(=x+iy) complex variable.
\delta arbitrary small positive constant.
primes derivatives with respect to argument.

The main functions treated in this chapter are the Airy functions \mathop{\mathrm{Ai}\/}\nolimits\!\left(z\right) and \mathop{\mathrm{Bi}\/}\nolimits\!\left(z\right), and the Scorer functions \mathop{\mathrm{Gi}\/}\nolimits(z) and \mathop{\mathrm{Hi}\/}\nolimits(z) (also known as inhomogeneous Airy functions).

Other notations that have been used are as follows: \mathop{\mathrm{Ai}\/}\nolimits\!\left(-x\right) and \mathop{\mathrm{Bi}\/}\nolimits\!\left(-x\right) for \mathop{\mathrm{Ai}\/}\nolimits\!\left(x\right) and \mathop{\mathrm{Bi}\/}\nolimits\!\left(x\right) (Jeffreys (1928), later changed to \mathop{\mathrm{Ai}\/}\nolimits\!\left(x\right) and \mathop{\mathrm{Bi}\/}\nolimits\!\left(x\right)); U(x)=\sqrt{\pi}\mathop{\mathrm{Bi}\/}\nolimits\!\left(x\right), V(x)=\sqrt{\pi}\mathop{\mathrm{Ai}\/}\nolimits\!\left(x\right) (Fock (1945)); A(x)=3^{{-\ifrac{1}{3}}}\pi\mathop{\mathrm{Ai}\/}\nolimits\!\left(-3^{{-\ifrac{1}{3}}}x\right) (Szegö (1967, §1.81)); e_{0}(x)=\pi\mathop{\mathrm{Hi}\/}\nolimits(-x), \widetilde{e}_{0}(x)=-\pi\mathop{\mathrm{Gi}\/}\nolimits(-x) (Tumarkin (1959)).