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 A043716 #12 Mar 12 2022 13:04:08 %S A043716 1,2,3,4,5,6,7,8,9,10,11,12,14,28,42,56,70,84,98,112,126,140,154,168, %T A043716 170,171,172,173,174,175,176,177,178,179,180,181,183,195,196,198,199, %U A043716 200,201,202,203,204,205,206,207,208,209,210 %N A043716 Numbers whose base-13 representation has an odd number of runs. %t A043716 Select[Range[250],OddQ[Length[Split[IntegerDigits[#,13]]]]&] (* _Harvey P. Dale_, Jan 31 2016 *) %K A043716 nonn,base %O A043716 1,2 %A A043716 _Clark Kimberling_