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 A053913 #8 Aug 11 2024 14:41:32
%S A053913 1,81,11881,78881777881,11187111187877881,77878887787187881
%N A053913 Squares composed of digits {1,7,8}.
%H A053913 P. De Geest, <a href="https://www.worldofnumbers.com/threedigits.htm">Squares containing at most three distinct digits, Index entries for related sequences</a>
%Y A053913 Cf. A053912.
%K A053913 nonn,base,more
%O A053913 1,2
%A A053913 _Patrick De Geest_, Mar 15 2000