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 A202172 #15 Jan 17 2025 15:05:17
%S A202172 0,4,400,484,40000,40804,48400,88804,4000000,4008004,4080400,4088484,
%T A202172 4840000,4848804,8880400,400000000,400080004,400800400,400880484,
%U A202172 408040000,408848400,484000000,484088004,484880400,840884004,888040000,40000000000,40000800004
%N A202172 Squares containing only the digits 0, 4 or 8.
%F A202172 a(n)=A202170(n)^2
%t A202172 Select[Range[0, 400000]^2, Complement[Union[IntegerDigits[#]], {0, 4, 8}] == {} &] (* _T. D. Noe_, Dec 21 2011 *)
%t A202172 Select[FromDigits/@Tuples[{0,4,8},11],IntegerQ[Sqrt[#]]&] (* _Harvey P. Dale_, Apr 19 2019 *)
%o A202172 (PARI) for(i=0,99999,setminus(Set(Vec(Str(i^2))),Vec("048")) || print1(i^2,","))
%Y A202172 Cf. A030098.
%K A202172 nonn,base
%O A202172 1,2
%A A202172 _M. F. Hasler_, Dec 13 2011