Smallest number that requires n iterations of the bi-unitary totient function (A116550) to reach 1.

Terms

a(0) =2a(1) =3a(2) =4a(3) =5a(4) =8a(5) =9a(6) =13a(7) =16a(8) =17a(9) =24a(10) =25a(11) =35a(12) =44a(13) =63a(14) =64a(15) =91a(16) =97a(17) =128a(18) =193a(19) =221a(20) =259a(21) =324a(22) =353a(23) =391a(24) =477a(25) =702a(26) =929a(27) =1188a(28) =1269a(29) =1589