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 A058428 #12 Jul 17 2025 08:20:22
%S A058428 9,2209,29929,299209,2900209,290200922209,2999229009299090209220929,
%T A058428 9009222020020222999909020009,9290090909029029202290909290992929,
%U A058428 22922009029909029220029029909020009,22220990020022929092929022220290920900929
%N A058428 Squares composed of digits {0,2,9}, not ending with zero.
%H A058428 Patrick De Geest, <a href="https://www.worldofnumbers.com/threedigits.htm">Index to related sequences</a>.
%H A058428 Hisanori Mishima, <a href="https://www.asahi-net.or.jp/~KC2H-MSM/mathland/math02/math0210.htm#029">Sporadic tridigital solutions</a>.
%F A058428 a(n) = A058427(n)^2. - _Elmo R. Oliveira_, Jul 16 2025
%Y A058428 Cf. A058427.
%K A058428 nonn,base,hard,more
%O A058428 1,1
%A A058428 _Patrick De Geest_, Nov 15 2000
%E A058428 a(10) from Herman Jamke (hermanjamke(AT)fastmail.fm), Mar 30 2008
%E A058428 a(11) from Mishima's website added by _Elmo R. Oliveira_, Jul 16 2025