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 A053969 #16 Aug 11 2024 14:41:32
%S A053969 576,676,5776,756767765776,6667676657766656676,
%T A053969 5677575655766577766776565776,5757665766657575655756675556,
%U A053969 665556775565576667756557666775667776,777666657567776675657756675676567555755556,6565656667556566576676575665776756666556676
%N A053969 Squares composed of digits {5,6,7}.
%H A053969 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 A053969 Author?, <a href="http://web.archive.org/web/20080708203024/http://blue.kakiko.com/mmrmmr/htm/eqtn06.html">Source</a>(<a href="http://web.archive.org/web/20060426155831/http://blue.kakiko.com/mmrmmr/txt/eqtn06.txt">txt</a>)
%H A053969 H. Mishima, <a href="http://www.asahi-net.or.jp/~KC2H-MSM/mathland/math02/math0210.htm#567">Squares consisted of 3 different digits</a>
%F A053969 a(n) = A053968(n)^2.
%Y A053969 Cf. A053968.
%K A053969 nonn,base
%O A053969 1,1
%A A053969 _Patrick De Geest_, Mar 15 2000
%E A053969 More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 03 2005
%E A053969 Two more terms from _Jon E. Schoenfield_, Sep 04 2006
%E A053969 Three more terms from Mishima's website added by _Max Alekseyev_, May 02 2011