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 A131573 #3 Mar 30 2012 18:49:09 %S A131573 149,298,334,472,667,745,882,1054,1055,1056,1057,1058,1490,1491,1492, %T A131573 1493,1825,1826,1827,2108,2109,2356,2357,2581,2582,2788,2789,2980, %U A131573 2981,3161,3162,3332,3333,3334,3335,3336,3337,3338,3339,3340,3341,3342,3343 %N A131573 Numbers whose square starts with 3 identical digits. %e A131573 149^2 = 22201. %t A131573 Select[Range[10, 5000], Length[Union[Take[IntegerDigits[ #^2], 3]]] == 1 &] %K A131573 base,nonn %O A131573 1,1 %A A131573 _Tanya Khovanova_, Aug 28 2007