One half of the even Markoff nunbers.

Terms

a(0) =1a(1) =17a(2) =97a(3) =305a(4) =3233a(5) =5473a(6) =18833a(7) =31105a(8) =98209a(9) =323009a(10) =639409a(11) =1006337a(12) =1762289a(13) =3726689a(14) =5742577a(15) =10015585a(16) =10765889a(17) =31622993a(18) =102636481a(19) =126595633a(20) =187990673a(21) =323536049a(22) =567451585a(23) =737853073a(24) =1075619873a(25) =3224987137a(26) =3342169921a(27) =10182505537a(28) =12396671585a(29) =25065271937