a(n) = position of n in A026204.

Terms

a(0) =2a(1) =1a(2) =5a(3) =3a(4) =7a(5) =9a(6) =11a(7) =4a(8) =13a(9) =14a(10) =16a(11) =18a(12) =20a(13) =6a(14) =22a(15) =8a(16) =24a(17) =26a(18) =28a(19) =10a(20) =31a(21) =32a(22) =34a(23) =36a(24) =38a(25) =12a(26) =41a(27) =42a(28) =44a(29) =46