After a(1) = 1, the sequence is always extended with the smallest divisor d (not yet present in the sequence) of the last term t. If d doesn't exist, we extend the sequence with tt (t concatenated to itself). If tt doesn't produce a new d, we extend the sequence with ttt, etc. See the Comments section for more details.
A348871
After a(1) = 1, the sequence is always extended with the smallest divisor d (not yet present in the sequence) of the last term t. If d doesn't exist, we extend the sequence with tt (t concatenated to itself). If tt doesn't produce a new d, we extend the sequence with ttt, etc. See the Comments section for more details.
Terms
- a(0) =1a(1) =11a(2) =111a(3) =3a(4) =33a(5) =333a(6) =9a(7) =99a(8) =999a(9) =27a(10) =2727a(11) =101a(12) =101101a(13) =7a(14) =77a(15) =777a(16) =21a(17) =2121a(18) =303a(19) =303303a(20) =13a(21) =1313a(22) =131313a(23) =37a(24) =3737a(25) =373737a(26) =39a(27) =3939a(28) =393939a(29) =63
External references
- oeis: A348871