Just another sequence!!

Please give the next 4 terms of the following sequence. Consider it an intellectual amusement and thanks!:

1, 4, 18, 48, 100, 180, 294, 448, 648...........

$\small{ \begin{array}{rcrcrcrcrcrcrcrcrcr} 1 &,& 4 &,& 18&,& 48&,& 100&,& 180&,& 294&,& 448&,& 648&,& \cdots\\ 1 &,& 2\cdot 2 &,&3\cdot 6&,&4\cdot 12&,&5\cdot 20&,&6\cdot 30&,&7\cdot 42&,&8\cdot 56&,&9\cdot 72&,& \cdots\\ 1 &,& 2\cdot 2\cdot 1 &,&3\cdot 3\cdot 2&,&4\cdot 4\cdot 3 &,&5\cdot 5\cdot 4&,&6\cdot 6\cdot 5&,&7\cdot 7\cdot 6&,&8\cdot 8\cdot 7&,&9\cdot 9\cdot 8&,& \cdots \end{array}\\ \begin{array}{lcl} \\ \mathbf{a_1} &\mathbf{=}& \mathbf{1}\\ \mathbf{a_n }& \mathbf{=}& \mathbf{ n^2\cdot (n-1) \qquad n> 1} \\\\ a_{10} &=& 10^2\cdot 9 = 900 \\ a_{11} &=& 11^2\cdot 10 = 1210 \\ a_{12} &=& 12^2\cdot 11 = 1584 \\ a_{13} &=& 13^2\cdot 12 = 2028 \\ \end{array} }$

This is complicated.

Does this involve patterns?

Of course!.

Here is a simpler way of doing this:

nth term=n^3 - n^2

10th=10^3 - 10^2

11th=11^3 - 11^2

12th=12^3 - 12^2

13th=13^3 -13^2

Nice Heureka  !!   

what is 2,4,6,8 23rd term