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 A043702 #10 Jun 18 2021 22:36:46 %S A043702 13,15,16,17,18,19,20,21,22,23,24,25,26,27,29,30,31,32,33,34,35,36,37, %T A043702 38,39,40,41,43,44,45,46,47,48,49,50,51,52,53,54,55,57,58,59,60,61,62, %U A043702 63,64,65,66,67,68,69,71,72,73,74,75,76,77 %N A043702 Numbers whose base-13 representation has an even number of runs. %t A043702 Select[Range[100],EvenQ[Length[Split[IntegerDigits[#,13]]]]&] (* _Harvey P. Dale_, Aug 22 2015 *) %K A043702 nonn,base %O A043702 1,1 %A A043702 _Clark Kimberling_