191 7-18.] Reduction-formula for Functions of Second Kind. 69 
/ 
The functions V 0 or A 0 may be reduced, by a slight change of variable, to 
the error-function Erf (z). 
These examples will suffice to show how this general method must be 
used for the reduction of functions of the second kind. 
Other functions to which a similar treatment may be applied are the 
Jacobean polynomials F n (z), which can be written F ( — n, a-\-n\ y ; z) and 
the confluent hypergeometric function W k>m (z) when m — k is of the form 
n + i, n being an integer. 
(Issued separately May 29, 1918.) 
