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 A103543 #14 Dec 22 2020 04:10:48
%S A103543 3,7,11,15,19,23,27,31,35,39,43,47,51,55,59,62,63,67,71,75,79,83,87,
%T A103543 91,95,99,103,107,111,115,119,123,126,127,131,135,139,143,147,151,155,
%U A103543 159,163,167,171,175,179,183,187,190,191,195,199,203,207,211,215,219,223
%N A103543 Consider those values of k for which A102370(k) = k: 0, 4, 8, 16, 20, 24, 32, 36, 40, 48, 52, 56, 64, ... and divide by 4: 0, 1, 2, 4, 5, 6, 8, 9, 10, 12, 13, 14, 16, 17, 18, 20, 21, 22, 24, ...; sequence gives missing numbers.
%H A103543 David Applegate, Benoit Cloitre, Philippe Deléham and N. J. A. Sloane, Sloping binary numbers: a new sequence related to the binary numbers [<a href="http://neilsloane.com/doc/slopey.pdf">pdf</a>, <a href="http://neilsloane.com/doc/slopey.ps">ps</a>].
%F A103543 Numbers of the form 4k+3 together with the terms of A103584.
%F A103543 It is shown in the reference that A102370(k) = k iff n == 0 (mod 4) and n does not belong to any of the arithmetic progressions Q_r := {2^(4r)*j - 4r, j >= 1} for r = 1, 2, 3, ...
%F A103543 In other words, the sequence consists of the numbers of the form j*2^(4k-2) - k for k >=2 and j >= 1.
%t A103543 f[n_] := Block[{k = 1, s = 0, l = Max[2, Floor[Log[2, n + 1] + 2]]}, While[k < l, If[ Mod[n + k, 2^k] == 0, s = s + 2^k]; k++ ]; s]; Complement[ Range[225], Select[ Range[900], f[ # ] == 0 &]/4] (* _Robert G. Wilson v_, Mar 23 2005 *)
%Y A103543 Cf. A102370, A103584.
%K A103543 nonn,easy,base
%O A103543 1,1
%A A103543 _N. J. A. Sloane_, Mar 23 2005
%E A103543 More terms from _Robert G. Wilson v_, Mar 23 2005