a(n) = n^6*(4*n+3).

Terms

a(0) =0a(1) =7a(2) =704a(3) =10935a(4) =77824a(5) =359375a(6) =1259712a(7) =3647119a(8) =9175040a(9) =20726199a(10) =43000000a(11) =83263367a(12) =152285184a(13) =265474495a(14) =444242624a(15) =717609375a(16) =1124073472a(17) =1713767399a(18) =2550916800a(19) =3716624599a(20) =5312000000a(21) =7461652527a(22) =10317571264a(23) =14063409455a(24) =18919194624a(25) =25146484375