Concentric 17-gonal numbers.

Terms

a(0) =0a(1) =1a(2) =17a(3) =35a(4) =68a(5) =103a(6) =153a(7) =205a(8) =272a(9) =341a(10) =425a(11) =511a(12) =612a(13) =715a(14) =833a(15) =953a(16) =1088a(17) =1225a(18) =1377a(19) =1531a(20) =1700a(21) =1871a(22) =2057a(23) =2245a(24) =2448a(25) =2653a(26) =2873a(27) =3095a(28) =3332a(29) =3571