a(n) = 1 + 2*n + n^2 + 2*n^3 + n^4.

Terms

a(0) =1a(1) =7a(2) =41a(3) =151a(4) =409a(5) =911a(6) =1777a(7) =3151a(8) =5201a(9) =8119a(10) =12121a(11) =17447a(12) =24361a(13) =33151a(14) =44129a(15) =57631a(16) =74017a(17) =93671a(18) =117001a(19) =144439a(20) =176441a(21) =213487a(22) =256081a(23) =304751a(24) =360049a(25) =422551a(26) =492857a(27) =571591a(28) =659401a(29) =756959