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 A054032 #13 Oct 27 2023 22:00:46
%S A054032 32,33,36,37,42,43,44,48,49,51,52,53,54,55,57,59,61,64,66,69,71,72,73,
%T A054032 74,78,79,82,84,86,87,89,93,95,96,98,99,103,104,105,106,112,114,115,
%U A054032 123,125,127,130,132,135,138,139,140,143,145,146,151,155,156,157,158
%N A054032 Numbers n such that n^2 contains exactly 4 different digits.
%H A054032 T. D. Noe, <a href="/A054032/b054032.txt">Table of n, a(n) for n = 1..10000</a>
%p A054032 f := []; for i from 0 to 200 do if nops({op(convert(i^2,base,10))})=4 then f := [op(f),i] fi; od; f;
%t A054032 t = {}; n = -1; While[Length[t] < 50, n++; If[Length[Union[IntegerDigits[n^2]]] == 4, AppendTo[t, n]]] (* _T. D. Noe_, Apr 26 2013 *)
%o A054032 (PARI) is(n)=#Set(digits(n^2))==4 \\ _Charles R Greathouse IV_, Feb 11 2017
%Y A054032 Cf. A016069, A054031, A054033, A054034, A054035, A054036, A054037, A054038, A054039.
%K A054032 nonn,base
%O A054032 1,1
%A A054032 _Asher Auel_, Feb 29 2000