Humbert polynomials

In mathematics, the Humbert polynomials π^λ
_n,m(x) are a generalization of Pincherle polynomials introduced by Humbert (1921) given by the generating function

${\displaystyle \displaystyle (1-mxt+t^{m})^{-\lambda }=\sum _{n=0}^{\infty }\pi _{n,m}^{\lambda }(x)t^{n}}$

Boas & Buck (1958, p.58).