Essentially the same as A003136.

Terms

a(0) =1a(1) =3a(2) =4a(3) =7a(4) =9a(5) =12a(6) =13a(7) =16a(8) =19a(9) =21a(10) =25a(11) =27a(12) =28a(13) =31a(14) =36a(15) =37a(16) =39a(17) =43a(18) =48a(19) =49a(20) =52a(21) =57a(22) =61a(23) =63a(24) =64