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 A033017 #18 Aug 14 2021 02:16:46 %S A033017 5,10,15,21,42,63,80,85,90,95,160,165,170,175,240,245,250,255,320,336, %T A033017 341,346,351,362,383,640,661,672,677,682,687,703,960,981,1002,1008, %U A033017 1013,1018,1023,1280,1285,1290,1295,1344,1360,1365 %N A033017 Numbers whose base-4 expansion has no run of digits with length < 2. %H A033017 Vincenzo Librandi, <a href="/A033017/b033017.txt">Table of n, a(n) for n = 1..1600</a> %t A033017 Select[Range[1400],Min[Length/@Split[IntegerDigits[#,4]]]>1&] (* _Harvey P. Dale_, Jun 05 2013 *) %Y A033017 Cf. A007090. Supersequence of A033002. %K A033017 nonn,base %O A033017 1,1 %A A033017 _Clark Kimberling_