a(n) = c([ n/2 ]) + n, with a(1) = 1, c = complement to a.

Terms

a(0) =1a(1) =4a(2) =5a(3) =7a(4) =8a(5) =12a(6) =13a(7) =17a(8) =18a(9) =20a(10) =21a(11) =23a(12) =24a(13) =28a(14) =29a(15) =31a(16) =32a(17) =34a(18) =35a(19) =39a(20) =40a(21) =44a(22) =45a(23) =49a(24) =50a(25) =52a(26) =53a(27) =55a(28) =56a(29) =60