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 A029774 #19 Aug 29 2023 04:23:48
%S A029774 0,1,10,100,235,1000,1049,1235,2350,2983,4762,4832,10000,10376,10490,
%T A029774 10493,10496,10923,11205,12335,12350,12385,12450,12650,14290,14829,
%U A029774 16205,17923,18235,18376,20495,22450,23500,23506,23566,24605
%N A029774 Numbers k in which the digits of k^2 appear.
%H A029774 Harvey P. Dale, <a href="/A029774/b029774.txt">Table of n, a(n) for n = 1..3001</a>
%F A029774 a(n) = sqrt(A029775(n)). - _Sean A. Irvine_, Mar 04 2020
%e A029774 235^2 = 55225, whose digits are a subset of {2,3,5}.
%t A029774 dn2Q[n_]:=And@@(MemberQ[Union[IntegerDigits[n]],#]&/@Union[ IntegerDigits[ n^2]]); Select[Range[0,25000],dn2Q] (* _Harvey P. Dale_, Apr 10 2013 *)
%t A029774 Select[Range[0,25000],SubsetQ[IntegerDigits[#],IntegerDigits[#^2]]&] (* using SubsetQ function from Mathematica 10 *) (* _Harvey P. Dale_, Jul 13 2014 *)
%Y A029774 Cf. A029775.
%K A029774 nonn,base
%O A029774 1,3
%A A029774 _Patrick De Geest_