Characterization By Generating Functions
Polynomial sequences of binomial type are precisely those whose generating functions are formal (not necessarily convergent) power series of the form
where f(t) is a formal power series whose constant term is zero and whose first-degree term is not zero. It can be shown by the use of the power-series version of Faà di Bruno's formula that
The delta operator of the sequence is f−1(D), so that
Read more about this topic: Binomial Type
Famous quotes containing the word functions:
“Let us stop being afraid. Of our own thoughts, our own minds. Of madness, our own or others. Stop being afraid of the mind itself, its astonishing functions and fandangos, its complications and simplifications, the wonderful operation of its machinerymore wonderful because it is not machinery at all or predictable.”
—Kate Millett (b. 1934)