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 A043515 #14 Apr 24 2021 21:15:54 %S A043515 666,1666,2666,3666,4666,5666,6066,6166,6266,6366,6466,6566,6606,6616, %T A043515 6626,6636,6646,6656,6660,6661,6662,6663,6664,6665,6667,6668,6669, %U A043515 6676,6686,6696,6766,6866,6966,7666,8666,9666,10666 %N A043515 Numbers having three 6's in base 10. %H A043515 Jens Kruse Andersen, <a href="/A043515/b043515.txt">Table of n, a(n) for n = 1..1000</a> %t A043515 Select[Range[0, 10^7], DigitCount[#, 10, 6]==3&] (* _Vincenzo Librandi_, Sep 25 2017 *) %K A043515 nonn,base %O A043515 1,1 %A A043515 _Clark Kimberling_