Even octagonal pyramidal numbers (A002414).

Terms

a(0) =30a(1) =70a(2) =364a(3) =540a(4) =1386a(5) =1794a(6) =3480a(7) =4216a(8) =7030a(9) =8190a(10) =12420a(11) =14100a(12) =20034a(13) =22330a(14) =30256a(15) =33264a(16) =43470a(17) =47286a(18) =60060a(19) =64780a(20) =80410a(21) =86130a(22) =104904a(23) =111720a(24) =133926a(25) =141934a(26) =167860a(27) =177156a(28) =207090a(29) =217770