sum of series

[cgchayan]

what will be the sum of this series?
\Sigma nCr . 2r
where r = 0 to n

[l'Hôpital]

Hint:

\sum_{r=0}^n _nC_r \cdot 2^r = \sum_{r=0}^n _nC_r \cdot 2^r \cdot 1^{n-r}

[cgchayan]

thanx

[Sherard]

thanks for sharing information....