Incomplete Gamma fails for negative integer arguments
Subject: Incomplete Gamma fails for negative integer arguments
From: Dieter Kaiser
Date: Sun, 26 Oct 2008 23:13:17 +0100
It is clear that the power series of the Incomplete Gamma function can not work
for the cases I have reported. We have a Gamma function gamma(a+1+n) in the
denominator of the sum which is not defined for zero and negative integers.
After implementing this sum as the series
inf
===
\ (-z)^n
> --------
/ (a+n)*n!
===
n=0
I have no longer recognized the restriction of the algorithm.
Thus, I have implemented the numerically calculation for a parameter which is a
negative integer or zero via the Exponential Integral E.
Dieter Kaiser