Find the sum of the following series whose `n th` term is: `n(n+1)(n+4)`

Explanation

` T_n= n(n+1)(n+4)`


`t_n=n^3+5n^2+4n`


`S_n= sum n^3 + 5 sum n^2+ 4 sum n`


`[(n(n+1))/2]^2+(5n(n+1)(2n+1))/8+(4n(n+1))/2`


...