Arises from a construction of equiangular lines in complex space of dimension 2.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =5a(5) =9a(6) =15a(7) =26a(8) =45a(9) =77a(10) =133a(11) =229a(12) =394a(13) =679a(14) =1169a(15) =2013a(16) =3467a(17) =5970a(18) =10281a(19) =17705a(20) =30489a(21) =52505a(22) =90418a(23) =155707a(24) =268141a(25) =461761a(26) =795191a(27) =1369386a(28) =2358197a(29) =4061013