Number of orbits of length n under a map whose periodic points are counted by A027306.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =3a(5) =6a(6) =9a(7) =19a(8) =28a(9) =62a(10) =93a(11) =205a(12) =315a(13) =703a(14) =1091a(15) =2440a(16) =3855a(17) =8616a(18) =13797a(19) =30801a(20) =49929a(21) =111311a(22) =182361a(23) =405751a(24) =671088a(25) =1490409a(26) =2485504a(27) =5509504a(28) =9256395a(29) =20480421