Trajectory of 20 under prime factor concatenation procedure.

Terms

a(0) =20a(1) =2a(2) =2a(3) =5a(4) =3a(5) =3a(6) =5a(7) =5a(8) =5a(9) =11a(10) =61a(11) =11a(12) =4651a(13) =3a(14) =3a(15) =12739a(16) =17a(17) =194867a(18) =19a(19) =41a(20) =22073a(21) =709a(22) =273797a(23) =3a(24) =97a(25) =137a(26) =17791a(27) =11a(28) =3610337981a(29) =7