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\begin{align}
 & B_{0}(x) = 1 , B_{1}(x) = x-\frac{1}{2} \\ 
& B_{k+1}^\prime (x) = (k+1)B_{k}(x) ,k= 1,2,\dots 
\end{align}


\begin{LTR}
$ (1) B_{0}(x) = 1 , B_{1}(x) = x-\frac{1}{2} \\ 
(2) B_{k+1}^\prime (x) = (k+1)B_{k}(x) ,k= 1,2,\dots $
\end{LTR}



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