In ternary expansion of n, reading from right to left, digits occur in order ...,0,1,2,0,1,2,...

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =7a(5) =11a(6) =21a(7) =34a(8) =65a(9) =102a(10) =196a(11) =308a(12) =588a(13) =925a(14) =1766a(15) =2775a(16) =5299a(17) =8327a(18) =15897a(19) =24982a(20) =47693a(21) =74946a(22) =143080a(23) =224840a(24) =429240a(25) =674521a(26) =1287722a(27) =2023563a(28) =3863167a(29) =6070691