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 A098839 #11 Mar 14 2025 09:36:08
%S A098839 4,121,576,729,6084,10201,17424,18496,36481,51529,100489,124609,
%T A098839 184041,195364,410881,559504,674041,695556,732736,887364,896809,
%U A098839 966289,988036,1038361,1190281,1238769,1726596,1852321,2166784,2975625,3407716,3613801,3663396
%N A098839 Smith square numbers.
%H A098839 Donovan Johnson, <a href="/A098839/b098839.txt">Table of n, a(n) for n = 1..10000</a>
%H A098839 Shyam Sunder Gupta, <a href="https://doi.org/10.1007/978-981-97-2465-9_4">Smith Numbers</a>, Exploring the Beauty of Fascinating Numbers, Springer (2025) Ch. 4, 127-157.
%e A098839 a(2) = 121 because 121 is a Smith number as well as a square.
%t A098839 d[n_]:=IntegerDigits[n]; tr[n_]:=Transpose[FactorInteger[n]]; t={}; Do[If[!PrimeQ[n]&&Total[d[n]]==Total[d@tr[n][[1]]*tr[n][[2]],2],AppendTo[t,n]],{n,Range[2,1950]^2}]; t (* _Jayanta Basu_, Jun 04 2013 *)
%Y A098839 Cf. A006753.
%K A098839 base,nonn
%O A098839 1,1
%A A098839 _Shyam Sunder Gupta_, Oct 10 2004