Pochhammer symbol

polynomial

h19pochf.gif (1491 bytes)

From the gamma function the Pochhammer symbol or rising factorial (x)n can be derived, in the following way:
y = Γ(x+n) / Γ(x).

The function can be found in series expansions for hypergeometric functions.

It is evident that on places where the gamma function has infinite values, the Pochhammer symbol has definite values.