Any help? I'm having trouble finding the 0th and 15th terms for this geometric sequence.

0th term
[tex]T_0=\frac{4}{27}andthe15thterm=T_{15}=19,131,876_{}^{}[/tex]By formula, the nth term of a G.P. is given by,
[tex]\begin{gathered} T_n=ar^{n-1},where,r=\frac{T_2}{T_1}_{}=\frac{T_3}{T_2}=\frac{12}{4}=\frac{36}{12}=3 \\ \end{gathered}[/tex][tex]undefined[/tex]