The sum of $1^3 + 2^3 + 3^3 + 4^3 + \dots + 15^3$ is

If the $n^{th}$ term of a series is $n(n + 1)$,then the sum of its $n$ terms is......

The sum of $n$ terms of the series $1^{3}+3^{3}+5^{3}+7^{3}+\ldots$ is

If the sum of the series $1^2 + 2 \cdot 2^2 + 3^2 + 2 \cdot 4^2 + 5^2 + \dots + 2 \cdot (n-1)^2 + n^2$ (when $n$ is odd) is to be determined,given that for even $n$,the sum is $\frac{n(n+1)^2}{2}$,find the sum when $n$ is odd.

$\sum\limits_{r = 1}^n {\sum\limits_{m = 1}^r {m} } = \dots$

The $20^{th}$ term of the series $2 \times 4 + 4 \times 6 + 6 \times 8 + \dots$ will be