# binomial coefficient

• Apr 18th 2012, 08:42 AM
Stuck Man
binomial coefficient
&#40;1&#43;x&#41;&#94;-0.5 - Wolfram|Alpha

I don't understand the coefficient of the general term given when mod. x <1. I have only seen positive integers before.
• Apr 18th 2012, 08:55 AM
FernandoRevilla
Re: binomial coefficient
Quote:

Originally Posted by Stuck Man
I don't understand the coefficient of the general term given when mod. x <1. I have only seen positive integers before.

If $p\in\mathbb{R},\;n\in \mathbb{N}$ we define $\displaystyle\binom{p}{n}=\dfrac{p(p-1)\ldots (p-n+1)}{n!}.$ For example $\displaystyle\binom{-0.5}{3}=\dfrac{(-0.5)(-0.5-1)(-0.5-2)}{3!}=\ldots$
• Apr 18th 2012, 09:10 AM
Stuck Man
Re: binomial coefficient
Thanks. I thought that way of evaluating nCr was simply convenient sometimes.