Image of n after 3k iterates of '3x+1' map (k large).

Terms

a(0) =1a(1) =2a(2) =2a(3) =4a(4) =4a(5) =4a(6) =2a(7) =1a(8) =2a(9) =1a(10) =4a(11) =1a(12) =1a(13) =4a(14) =4a(15) =2a(16) =1a(17) =4a(18) =4a(19) =2a(20) =2a(21) =1a(22) =1a(23) =2a(24) =4a(25) =2a(26) =1a(27) =1a(28) =1a(29) =1