Geometric sequence

a=3 and r=2
Un=a(r^(n-1)) U16=a(r^15)=3(2^15)=3(32768)=98304

$r=\dfrac{6}{3}=\dfrac{12}{6}=2$

$a_n=a_1r^{n-1}$

$a_{16}=a_1r^{15}=3(2^{15})=$ $\color{#D61F06}\boxed{98304}$

The value of the $n_x$ th term in this sequence is equivalent to $2 ^ {x-1}*3$ .

Plugging 16 in, we get $n_{16}=2^{16-1}*3=2^{15}*3=32768*3=98304$