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 A043490 #15 Apr 24 2021 21:08:41 %S A043490 100,200,300,400,500,600,700,800,900,1001,1002,1003,1004,1005,1006, %T A043490 1007,1008,1009,1010,1020,1030,1040,1050,1060,1070,1080,1090,1100, %U A043490 1200,1300,1400,1500,1600,1700,1800,1900,2001,2002 %N A043490 Numbers having two 0's in base 10. %H A043490 Daniel Starodubtsev, <a href="/A043490/b043490.txt">Table of n, a(n) for n = 1..10000</a> %t A043490 Select[Range[2100],DigitCount[#,10,0]==2&] (* _Harvey P. Dale_, Aug 29 2012 *) %Y A043490 Subsequence of A011540. %K A043490 nonn,base %O A043490 1,1 %A A043490 _Clark Kimberling_