This is LaTeX code:
[latex]
$\begin{equation*}\begin{array}{l} 2^{n+2} + 2n + 1 = 2^{n+3} - n - 4 = 2 \cdot 2^{n+2} - n - 4 \\ 2 \cdot 2^{n+2} - 2^{n+2} = n + 4 + 2n + 1 = 0 \\ 2^{n+2} = 3n + 5 \end{array}\end{equation*}$
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