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User talk:Baijiangchen

Revision as of 23:20, 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: W(n)=(2n-1)!!")
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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)!!

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