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 A273105 #17 May 03 2021 16:31:09
%S A273105 0,2,2,6,3,9,8,14,5,15,10,20,15,25,20,30,9,27,14,32,19,37,24,42,29,47,
%T A273105 34,52,39,57,44,62,17,51,22,56,27,61,32,66,37,71,42,76,47,81,52,86,57,
%U A273105 91,62,96,67,101,72,106,77,111,82,116,87,121,92,126,33,99
%N A273105 a(n) = A038572(n) + A006257(n), sum of the two numbers obtained by rotating the binary representation of n by one place to the right and to the left.
%t A273105 Table[FromDigits[RotateRight@ #, 2] + FromDigits[RotateLeft@ #, 2] &@ IntegerDigits[n, 2], {n, 0, 65}] (* _Michael De Vlieger_, May 17 2016 *)
%o A273105 (Python)
%o A273105 print('0', end=',')
%o A273105 for n in range(1,1000):
%o A273105 BL = len(bin(n))-2
%o A273105 x = (n>>1) + ((n&1) << (BL-1)) # A038572(n)
%o A273105 x+= (n*2) - (1<<BL) + 1 # A006257(n) for n>0
%o A273105 print(str(x), end=',')
%Y A273105 Cf. A006257, A038572, A088161, A088163.
%K A273105 nonn,base,easy
%O A273105 0,2
%A A273105 _Alex Ratushnyak_, May 15 2016