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 A045859 #24 Aug 09 2021 04:58:22
%S A045859 23,24,71,72,73,74,75,76,77,224,225,226,227,228,229,230,231,232,233,
%T A045859 234,235,236,237,238,239,240,241,242,243,244,708,709,710,711,712,713,
%U A045859 714,715,716,717,718,719,720,721,722,723,724,725,726,727,728,729,730
%N A045859 Numbers whose square has initial digit '5'.
%C A045859 A000030(A000290(a(n))) = 5. [_Reinhard Zumkeller_, Mar 07 2010]
%H A045859 Seiichi Manyama, <a href="/A045859/b045859.txt">Table of n, a(n) for n = 1..10000</a>
%t A045859 Rest[Table[If[First[IntegerDigits[n^2]] == 5, n, 0], {n, 1, 2500}]// Union] (* _José María Grau Ribas_, Feb 15 2010 *)
%o A045859 (PARI) isok(n) = digits(n^2)[1] == 5; \\ _Michel Marcus_, Dec 13 2017
%Y A045859 Cf. A045788.
%K A045859 nonn,base
%O A045859 1,1
%A A045859 _Jeff Burch_