Number of iterations until 3n reaches 153 under x goes to sum of cubes of digits map.

Terms

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