This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A333415 #45 May 20 2024 10:30:45
%S A333415 1,11,101,111,1001,1101,1011,1111,10001,11001,10101,11101,10011,11011,
%T A333415 10111,11111,100001,110001,101001,111001,100101,110101,101101,111101,
%U A333415 100011,110011,101011,111011,100111,110111,101111,111111,1000001,1100001,1010001,1110001,1001001
%N A333415 Odd positive integers in base 2 read backwards.
%H A333415 Robert Israel, <a href="/A333415/b333415.txt">Table of n, a(n) for n = 1..10000</a>
%F A333415 From _Michel Marcus_, Apr 23 2020: (Start)
%F A333415 a(n) = A007088(A145341(n)).
%F A333415 a(n) = A004086(A099821(n)). (End)
%p A333415 f:= proc(n) local L,i;
%p A333415 L:= convert(n,base,2);
%p A333415 add(L[-i]*10^(i-1),i=1..nops(L));
%p A333415 end proc
%p A333415 map(f, [seq(i,i=1..100,2)]); # _Robert Israel_, May 19 2024
%t A333415 Table[FromDigits[Reverse[IntegerDigits[n, 2]]], {n, 1, 75, 2}] (* _Amiram Eldar_, Apr 27 2020 *)
%o A333415 (PARI) a(n) = fromdigits(Vecrev(binary(2*n-1))); \\ _Michel Marcus_, May 19 2024
%Y A333415 Cf. A007088, A145341.
%Y A333415 Cf. A004086, A099821.
%K A333415 nonn,base
%O A333415 1,2
%A A333415 _Devansh Singh_, Mar 20 2020
%E A333415 New name, a(1)=1 and more terms from _Michel Marcus_, Apr 23 2020