Finding the sum of Binomial Coefficients

Question

The question says to find the value of $$\binom{n}{1} \cdot \left( \sum ^1 _ {r=0} \binom{1}{r}\right) + \binom{n}{2} \cdot \left( \sum ^2 _ {r=0} \binom{2}{r}\right) + \binom{n}{3} \cdot \left( \sum ^3 _ {r=0} \binom{3}{r}\right) \ldots \binom{n}{n} \cdot \left( \sum ^n _ {r=0} \binom{n}{r}\right)$$ I wrote $$\left( \sum ^n _ {r=0} \binom{n}{r}\right) = 2^n$$ Which gives us a series like this, $$\binom{n}{1} \cdot 2 + \binom{n}{2} \cdot 2^2 + \ldots \binom{n}{n} \cdot 2^n$$ But I am not able to figure out what to do from here.
Any help would be much appreciated.