a(n) is a binary encoded version of A355057(n).

Terms

a(0) =0a(1) =0a(2) =1a(3) =3a(4) =6a(5) =7a(6) =13a(7) =15a(8) =27a(9) =59a(10) =122a(11) =123a(12) =243a(13) =499a(14) =501a(15) =511a(16) =1007a(17) =2031a(18) =4047a(19) =8143a(20) =16271a(21) =32655a(22) =65422a(23) =65423a(24) =130831a(25) =261903a(26) =523791a(27) =1048079a(28) =2096651a(29) =2096671