a(n+3) = a(n) + 24*n + 40, a(0)=0, a(1)=5, a(2)=19.

Terms

a(0) =0a(1) =5a(2) =19a(3) =40a(4) =69a(5) =107a(6) =152a(7) =205a(8) =267a(9) =336a(10) =413a(11) =499a(12) =592a(13) =693a(14) =803a(15) =920a(16) =1045a(17) =1179a(18) =1320a(19) =1469a(20) =1627a(21) =1792a(22) =1965a(23) =2147a(24) =2336a(25) =2533a(26) =2739a(27) =2952a(28) =3173a(29) =3403