Respuesta :
[tex]\bf \begin{array}{|cc|ll} \cline{1-2} value&term\\ \cline{1-2} \blacktriangle&3^0\\&\\ \blacktriangle\blacktriangle\blacktriangle&3^1\\&\\ \blacktriangle\blacktriangle\blacktriangle&3^2\\ \blacktriangle\blacktriangle\blacktriangle&\\ \blacktriangle\blacktriangle\blacktriangle&\\ \cline{1-2} \end{array}~\hspace{10em}\displaystyle\sum\limits_{i=0}^{14}~3^i[/tex]