Răspuns :
[tex]a = {2}^{n + 1} \times {3}^{n} + {2}^{n} \times {3}^{n + 2} \\ \\ \\ a = {2}^{n} \times {2}^{1} \times {3}^{n} + {2}^{n} \times {3}^{n} \times {3}^{2} \\ \\ \\ a = {6}^{n} \times {2}^{1} + {6}^{n} \times {3}^{2} \\ \\ \\ a = {6}^{n} ( {2}^{1} + {3}^{2} ) \\ \\ \\ a = {6}^{n} \times 11[/tex]