Pell oblongs.

Terms

a(0) =1a(1) =3a(2) =21a(3) =119a(4) =697a(5) =4059a(6) =23661a(7) =137903a(8) =803761a(9) =4684659a(10) =27304197a(11) =159140519a(12) =927538921a(13) =5406093003a(14) =31509019101a(15) =183648021599