a(n) is 2^n represented in bijective base-9 numeration.

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =17a(5) =35a(6) =71a(7) =152a(8) =314a(9) =628a(10) =1357a(11) =2725a(12) =5551a(13) =12212a(14) =24424a(15) =48848a(16) =98797a(17) =218715a(18) =438531a(19) =878162a(20) =1867334a(21) =3845668a(22) =7792447a(23) =16694895a(24) =34499911a(25) =69121922a(26) =149243944a(27) =299487988a(28) =619987187a(29) =1342185385