This is LaTeX code:

[latex]
\frac{n}{2}+2^{n}*\frac{1}{2^{n+1}} = \frac{n}{2}+\frac{1}{2} = \frac{n+1}{2} < 1+\frac{1}{2}+\frac{1}{2^{n+1}-1} 
[/latex]