Question

What does a double factorial do?

Answer 1

\[\large {f^n}(x) = \frac{{\prod\limits_{k = 0}^n {(2k + 1)} }}{{{2^n}}}{(1 - x)^{\frac{{( - 2n - 1)}}{2}}} \]I want to replace the numerator with something that will give me odd multiples starting at 1.. EG, 1*3*5*7 when n=4. I read about a double factorial that may be able to do this?

Answer 2

http://screencast.com/t/P7qpCrOAnGox

Answer 3

see if this helps:
http://mathworld.wolfram.com/DoubleFactorial.html
ive never heard of them before now so thats all i got