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 A058434 #6 Aug 11 2024 14:41:33
%S A058434 9,939099093390990009
%N A058434 Squares composed of digits {0,3,9}, not ending with zero.
%H A058434 P. De Geest, <a href="https://www.worldofnumbers.com/threedigits.htm">Index to related sequences</a>
%H A058434 Hisanori Mishima, <a href="http://www.asahi-net.or.jp/~KC2H-MSM/mathland/math02/math0210.htm#039">Sporadic tridigital solutions</a>
%Y A058434 Cf. A058433.
%K A058434 nonn,base,hard,more,bref
%O A058434 1,1
%A A058434 _Patrick De Geest_, Nov 15 2000