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 A053955 #15 Jul 20 2025 10:36:38
%S A053955 4,9,49,44944,5555449,545549449,59554545444,459949959549955449,
%T A053955 555444595959444995959495549444,
%U A053955 495555459949459999994555545994544549499995545449
%N A053955 Squares composed of digits {4,5,9}.
%H A053955 Patrick De Geest, <a href="https://www.worldofnumbers.com/threedigits.htm">Squares containing at most three distinct digits, Index entries for related sequences</a>.
%H A053955 Hisanori Mishima <a href="https://www.asahi-net.or.jp/~KC2H-MSM/mathland/math02/math0210.htm">Squares consisted of 3 different digits</a>.
%F A053955 a(n) = A053954(n)^2. - _Elmo R. Oliveira_, Jul 19 2025
%Y A053955 Cf. A053954.
%K A053955 nonn,base,more
%O A053955 1,1
%A A053955 _Patrick De Geest_, Mar 15 2000
%E A053955 a(9)-a(10) from Mishima's webpage added by _Max Alekseyev_, May 18 2009