$$\left. \begin{array} { l } { \frac { i } { 2 } ( n + 1 ) ( n + 1 ) ( n + 1 ) n + 10 n ( n ) \times 10 + 10 a n + 10 n + 1 } \end{array} \right.$$
$\frac{in\left(n+1\right)^{3}}{2}+10an+100n^{2}+10n+1$
