Maximal term in Collatz-iteration started at 2^n+1.

Terms

a(0) =2a(1) =16a(2) =16a(3) =52a(4) =52a(5) =100a(6) =196a(7) =9232a(8) =9232a(9) =1540a(10) =3076a(11) =9232a(12) =12292a(13) =24580a(14) =49156a(15) =98308a(16) =196612a(17) =393220a(18) =786436a(19) =1572868a(20) =3145732a(21) =6291460a(22) =12582916a(23) =25165828a(24) =50331652a(25) =100663300a(26) =201326596a(27) =402653188a(28) =805306372a(29) =1610612740