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 A180018 #11 Nov 06 2022 07:48:47
%S A180018 0,0,1,1,3,3,4,4,7,7,-1,-1,1,1,2,2,6,6,7,7,0,0,1,1,4,4,5,5,7,7,-1,-1,
%T A180018 4,4,5,5,7,7,8,8,2,2,3,3,5,5,6,6,10,10,2,2,4,4,5,5,8,8,9,9,2,2,3,3,9,
%U A180018 9,10,10,12,12,4,4,7,7,8,8,10,10,11,11,6,6,7,7,9,9,10,10,13,13,5,5,7,7,8,8
%N A180018 Difference of sums of digits of n in decimal and in binary representation.
%H A180018 Reinhard Zumkeller, <a href="/A180018/b180018.txt">Table of n, a(n) for n = 0..10000</a>
%H A180018 <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a>
%F A180018 a(n) = A007953(n) - A000120(n);
%F A180018 a(A037308(n)) = 0;
%F A180018 a(A011557(n)) = 1 - A000120(A011557(n));
%F A180018 a(A000079(n)) = A007953(A000079(n)) - 1;
%F A180018 a(A002283(n)) = A008591(n) - A000120(A002283(n));
%F A180018 a(A000225(n)) = A007953(A000225(n)) - n.
%t A180018 Table[Total[IntegerDigits[n]]-Total[IntegerDigits[n,2]],{n,0,100}] (* _Harvey P. Dale_, Dec 27 2015 *)
%o A180018 (PARI) a(n) = sumdigits(n) - hammingweight(n); \\ _Michel Marcus_, Nov 06 2022
%Y A180018 Cf. A180017, A180019, A007088.
%Y A180018 Cf. A007953, A000120, A037308, A011557.
%Y A180018 Cf. A000079, A002283, A008591, A000225.
%K A180018 base,sign
%O A180018 0,5
%A A180018 _Reinhard Zumkeller_, Aug 06 2010