Difference between revisions of "User talk:Baijiangchen"

Line 11: Line 11:
 
==Sam's stuff==
 
==Sam's stuff==
 
Let <math>W(n)=\sum_{i=1}^{n}(\binom{i-1}{n-1}W(i-1)(x-i)!(2^{x-i}))</math>
 
Let <math>W(n)=\sum_{i=1}^{n}(\binom{i-1}{n-1}W(i-1)(x-i)!(2^{x-i}))</math>
 +
 +
Assume that for some integer <math>x</math>, <math>W(x)=(2x-1)!!</math>. We intend to show that <math>W(x+1)=(2(x+1)-1)!!=(2x+1)!!</math>.

Revision as of 00:27, 22 July 2012

If:

$W(0):=1$

$W(n):=\sum_{i=0}^{n-1}({n-1 \choose i}W(i)(x-i-1)!(2^{x-i-1}))$

Then:

$W(n)=(2n-1)!!$

Sam's stuff

Let $W(n)=\sum_{i=1}^{n}(\binom{i-1}{n-1}W(i-1)(x-i)!(2^{x-i}))$

Assume that for some integer $x$, $W(x)=(2x-1)!!$. We intend to show that $W(x+1)=(2(x+1)-1)!!=(2x+1)!!$.