13 Confluent Hypergeometric Functions13.2 Definitions and Basic Properties

§13.1 Special Notation

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

m integer.
n, s nonnegative integers.
x, y real variables.
z complex variable.
\delta arbitrary small positive constant.
\gamma Euler’s constant (§5.2(ii)).
\mathop{\Gamma\/}\nolimits\!\left(x\right) Gamma function (§5.2(i)).
\mathop{\psi\/}\nolimits\!\left(x\right) \ifrac{{\mathop{\Gamma\/}\nolimits^{{\prime}}}\!\left(x\right)}{\mathop{\Gamma\/}\nolimits\!\left(x\right)}.

The main functions treated in this chapter are the Kummer functions \mathop{M\/}\nolimits\!\left(a,b,z\right) and \mathop{U\/}\nolimits\!\left(a,b,z\right), Olver’s function \mathop{{\mathbf{M}}\/}\nolimits\!\left(a,b,z\right), and the Whittaker functions \mathop{M_{{\kappa,\mu}}\/}\nolimits\!\left(z\right) and \mathop{W_{{\kappa,\mu}}\/}\nolimits\!\left(z\right).

Other notations are: \mathop{{{}_{{1}}F_{{1}}}\/}\nolimits\!\left(a;b;z\right)16.2(i)) and \Phi(a;b;z) (Humbert (1920)) for \mathop{M\/}\nolimits\!\left(a,b,z\right); \Psi(a;b;z) (Erdélyi et al. (1953a, §6.5)) for \mathop{U\/}\nolimits\!\left(a,b,z\right); V(b-a,b,z) (Olver (1997b, p. 256)) for e^{z}\mathop{U\/}\nolimits\!\left(a,b,-z\right); \mathop{\Gamma\/}\nolimits\!\left(1+2\mu\right)\mathscr{M}_{{\kappa,\mu}} (Buchholz (1969, p. 12)) for \mathop{M_{{\kappa,\mu}}\/}\nolimits\!\left(z\right).

For an historical account of notations see Slater (1960, Chapter 1).