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[parent] Viewing Correction to 'gamma function'
On definition by scineram

Correction id: 5521
Filed on: 2005-01-01 21:44:03
Status: Rejected on 2005-03-17 16:46:54
Type: Meta/Minor

Correction text:
\usepackage{amssymb}
\usepackage{amsmath}
\usepackage{amsfonts}
\begin{document}
As I know, the integral definition is good for only $\mathcal{R}[z]>0$, because $\int_0^1 e^{-t}t^{z-1}dt$ is not necessarily convergent in the other half-plane. However, for $\mathcal{R}[x]>0$ this integral is equal to $\sum_{n=0}^\infty\frac{(-1)^n}{n!(z+n)}$, so the function can be extended to $\mathbb{C}\setminus\{-\mathbb{N}\}$ as $$\Gamma(z)=\sum_{n=0}^\infty\frac{(-1)^n}{n!(z+n)}+\int\limits_1^\infty e^{-t}t^{z-1}dt.$$

Comment from correction handler akrowne:
filer failed to follow up (see post to original correction)
Discussion
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gamma function complex def. by akrowne on 2005-01-12 16:27:31
I have a few questions about your correction.

First, I think you introduced an "x" at one point where you didn't mean to, and somewhere I think you used a greater-than instead of a less-than. Is this correct, and if so, can you provide the text of your correction with the modifications?

Secondly, isn't your summation expression of the complex gamma function equivalent to the product expression at the end of the entry? If so, should both be included, and a statement made of their equivalence, and potentialy steps shown or suggestions made about how to transform one to the other?

I think a major re-organization of the entry needs to be done, likely presenting just the real and natural cases of the gamma function first, then later presenting the complex gamma function, as this could get more complicated indefinitely =)

apk
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