Number of orbits of length n under the map whose periodic points are counted by A001641.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =3a(5) =4a(6) =7a(7) =10a(8) =17a(9) =26a(10) =44a(11) =68a(12) =115a(13) =184a(14) =306a(15) =500a(16) =835a(17) =1374a(18) =2301a(19) =3822a(20) =6409a(21) =10718a(22) =18028a(23) =30280a(24) =51077a(25) =86130a(26) =145641a(27) =246370a(28) =417600a(29) =708246