Does ∑ n = 1 ∞ n 4 2 n / 3 ( 2 n + 7 ) 4 {\displaystyle {\displaystyle \sum _{n=1}^{\infty }{\frac {n^{4}2^{n/3}}{(2n+7)^{4}}}}} converge or diverge? Justify your conclusion.
