a(0) = 1, a(n) = 1 + 2*3 + 4*5 + 6*7 + ... + (2n)*(2n+1) for n > 0.

Terms

a(0) =1a(1) =7a(2) =27a(3) =69a(4) =141a(5) =251a(6) =407a(7) =617a(8) =889a(9) =1231a(10) =1651a(11) =2157a(12) =2757a(13) =3459a(14) =4271a(15) =5201a(16) =6257a(17) =7447a(18) =8779a(19) =10261a(20) =11901a(21) =13707a(22) =15687a(23) =17849a(24) =20201a(25) =22751a(26) =25507a(27) =28477a(28) =31669a(29) =35091