Concentric 16-gonal numbers.

Terms

a(0) =0a(1) =1a(2) =16a(3) =33a(4) =64a(5) =97a(6) =144a(7) =193a(8) =256a(9) =321a(10) =400a(11) =481a(12) =576a(13) =673a(14) =784a(15) =897a(16) =1024a(17) =1153a(18) =1296a(19) =1441a(20) =1600a(21) =1761a(22) =1936a(23) =2113a(24) =2304a(25) =2497a(26) =2704a(27) =2913a(28) =3136a(29) =3361