[tex] \frac{ {6}^{n + 1} + {6}^{n} }{ {5}^{n + 2} - 6 \times {5}^{n} } = \frac{ {6}^{n} \times 6 + {6}^{n} }{ {5}^{n} \times 25 - 6 \times {5}^{n} } = \frac{ {6}^{n}(6 + 1) }{ {5}^{n} (25 - 6)} = \frac{ {6}^{n} \times 7}{ {5}^{n} \times 19 } \: - \: ireductibila[/tex]
