Trajectory of 3 under map n->9n+1 if n odd, n->n/2 if n even.

Terms

a(0) =3a(1) =28a(2) =14a(3) =7a(4) =64a(5) =32a(6) =16a(7) =8a(8) =4a(9) =2a(10) =1a(11) =10a(12) =5a(13) =46a(14) =23a(15) =208a(16) =104a(17) =52a(18) =26a(19) =13a(20) =118a(21) =59a(22) =532a(23) =266a(24) =133a(25) =1198a(26) =599a(27) =5392a(28) =2696a(29) =1348