Proof by induction that $2^n - 1 > n^2$ i want to prove that $\forall n\geq 5$ 
$$2^{n}-1 > n^{2}$$
so the basis is trivial, and in the induction step (n+1), i stuck. i get :  
$(n+1)^{2} =  n^{2} + 2n + 1 < (2^{n} -1)+ 2n+1 = 2^{n} + 2n $
what i need to do from here?
tnx!

Hint: $2^{n+1}-1 = 2\cdot (2^n - 1)+1$
