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 A053954 #12 Aug 11 2024 14:41:32
%S A053954 2,3,7,212,2357,23357,244038,678196107,745281554823038,
%T A053954 703957001491895099962643
%N A053954 Numbers k such that k^2 contains only digits {4,5,9}.
%H A053954 P. De Geest, <a href="https://www.worldofnumbers.com/threedigits.htm">Squares containing at most three distinct digits, Index entries for related sequences</a>
%H A053954 H. Mishima <a href="http://www.asahi-net.or.jp/~KC2H-MSM/mathland/math02/math0210.htm">Squares consisted of 3 different digits</a> [From _Max Alekseyev_, May 18 2009]
%Y A053954 Cf. A053955.
%K A053954 nonn,base,more
%O A053954 1,1
%A A053954 _Patrick De Geest_, Mar 15 2000
%E A053954 Two more terms from Mishima's webpage added by _Max Alekseyev_, May 18 2009