User:Baijiangchen
Revision as of 23:22, 21 July 2012 by Baijiangchen (talk | contribs) (Created page with "If: <math>W(0):=1</math> <math>W(n):=\sum_{i=0}^{n-1}({n-1 \choose i}W(i)(x-i-1)!(2^{x-i-1}))</math> Then: <math>W(n)=(2n-1)!!</math>")
If:
Then:
