A self-generating sequence (see Comments for definition).

Terms

a(0) =1a(1) =4a(2) =5a(3) =6a(4) =9a(5) =12a(6) =15a(7) =16a(8) =17a(9) =20a(10) =21a(11) =22a(12) =25a(13) =26a(14) =27a(15) =30a(16) =33a(17) =36a(18) =37a(19) =38a(20) =41a(21) =44a(22) =47a(23) =48a(24) =49a(25) =52a(26) =55a(27) =58a(28) =59a(29) =60