<r>I read your proof, dunrewpp. I think it is good and I like it.One thing I note that in your proof, how can you guarantee that N=1-b(n,0)+b(n,1)-b(n,2)+-?.+{(-1)^(n)}*b(n,n-1) is nonzero because of so many terms, which might be canceled out.The <URL url="http://en.wikipedia.org/wiki/Dirichlet%27s_...