Number of points in Z^n of norm <= 5.

Terms

a(0) =1a(1) =11a(2) =81a(3) =515a(4) =3121a(5) =16875a(6) =84769a(7) =394691a(8) =1733537a(9) =7129227a(10) =27634481a(11) =102386243a(12) =365127249a(13) =1256538091a(14) =4180101249a(15) =13457728387a(16) =41966634049a(17) =126929576971a(18) =373074639633