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 A058425 #46 Jul 16 2025 08:08:49
%S A058425 5,15,45,235,505,745,1415,1485,4495,5005,15985,50005,72495,469255,
%T A058425 500005,500505,1597505,1598515,4474955,5000005,5000505,5050005,
%U A058425 7085235,15008515,44949995,50000005,50000505,50005005,50500005,500000005,500000505,500005005,500254955,500500005
%N A058425 Numbers k such that k^2 contains only digits {0,2,5}, not ending with zero.
%C A058425 Most terms have a special pattern in that they have only digits 0 and 5 and could be written as Sum_{h=0..t} 5*10^f(h), where 2f(h), 2f(h)-1, and f(h1) + f(h2) are all distinct and f(0)=0 for the nonzero ending constraint. - _Zhao Hui Du_, Mar 12 2024
%H A058425 Zhao Hui Du, <a href="/A058425/b058425.txt">Table of n, a(n) for n = 1..5913</a>
%H A058425 Patrick De Geest, <a href="http://www.worldofnumbers.com/threedigits.htm">Index to related sequences</a>.
%H A058425 Hisanori Mishima, <a href="http://www.asahi-net.or.jp/~KC2H-MSM/mathland/math02/math0210.htm#025">Sporadic tridigital solutions</a>.
%Y A058425 Cf. A058426.
%K A058425 nonn,base
%O A058425 1,1
%A A058425 _Patrick De Geest_, Nov 15 2000
%E A058425 a(29)=50500005 inserted by _Georg Fischer_, Jan 12 2022