a(n) = (3*(2*n - 1)^2*((2*n - 1)^2 + 2) - 2*n + 3)/2 for n > 0.

Terms

a(0) =5a(1) =148a(2) =1011a(3) =3746a(4) =10081a(5) =22320a(6) =43343a(7) =76606a(8) =126141a(9) =196556a(10) =293035a(11) =421338a(12) =587801a(13) =799336a(14) =1063431a(15) =1388150a(16) =1782133a(17) =2254596a(18) =2815331a(19) =3474706a(20) =4243665a(21) =5133728a(22) =6156991a(23) =7326126a(24) =8654381a(25) =10155580a(26) =11844123a(27) =13734986a(28) =15843721a(29) =18186456