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%I #27 May 08 2022 08:47:48
%S 4,64,484,4624,8464,26244,28224,68644,228484,446224,824464,868624,
%T 2862864,8282884,8868484,22448644,26646244,44462224,82228624,82664464,
%U 222248464,284866884,662444644,866242624,4246868224,4444622224,6266622244,6282464644,6668682244,8264264464,8268628624
%N Squares whose digits are all positive and even.
%C Subset of A030098.
%C All terms end with 4, because when k^2 ends with 6, the tens digit of k^2 is always odd. - _Bernard Schott_, May 02 2022
%C The sequence is infinite because squares of the form 4 = 2^2, 64 = 8^2, 4624 = 68^2, 446224 = 668^2, 44462224 = 6668^2, ... (2*(10^k + 2) / 3 )^2 , k >= 0, are terms. - _Marius A. Burtea_, May 02 2022
%H Michael S. Branicky, <a href="/A103751/b103751.txt">Table of n, a(n) for n = 1..4198</a> (terms 1..180 from Marius A. Burtea)
%p a:=proc(n) if convert(convert((n^2),base,10),set) subset {2,4,6,8} then n^2 else fi end:seq(a(n),n=1..100000);
%t pevQ[n_]:=Module[{idn=IntegerDigits[n]},FreeQ[idn,0]&&And@@EvenQ[idn]]; Select[Range[70000]^2,pevQ] (* _Harvey P. Dale_, Jul 19 2013 *)
%o (PARI) isok(n) = my(d=digits(n)); vecmin(d) && (#select(x->(x%2), d) == 0);
%o lista(nn) = {my(list = List()); for (n=1, nn, if (isok(n^2), listput(list, n^2););); Vec(list);} \\ _Michel Marcus_, May 02 2022
%o (Magma) [n:n in [s*s:s in [1..100000]]| Set(Intseq(n)) subset {2,4,6,8}]; // _Marius A. Burtea_, May 02 2022
%Y Cf. A030098.
%K nonn,base
%O 1,1
%A _Emeric Deutsch_, Mar 28 2005
%E More terms from _Bernard Schott_, May 02 2022
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