position of n in A026245.

Terms

a(0) =1a(1) =4a(2) =2a(3) =3a(4) =8a(5) =9a(6) =5a(7) =6a(8) =13a(9) =16a(10) =17a(11) =7a(12) =20a(13) =21a(14) =24a(15) =10a(16) =27a(17) =30a(18) =31a(19) =11a(20) =12a(21) =35a(22) =38a(23) =14a(24) =15a(25) =42a(26) =43a(27) =46a(28) =18a(29) =49