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 A071135 #5 Aug 01 2018 10:29:06
%S A071135 557904400,1255284900,2231617600,508239242281,110723679691024,
%T A071135 267200559990920521,4624943568803015273104,89426738951269414045129,
%U A071135 106343953870710063227329,141828621071731373745001,153228095100765507880225,155946118585671902125225
%N A071135 Squares which repeat with at least two full periods when written in base 9.
%H A071135 Giovanni Resta, <a href="/A071135/b071135.txt">Table of n, a(n) for n = 1..15</a> (terms < 9^25)
%e A071135 23620^2 = 557904400 = 13857|13857 in base 9.
%e A071135 712909^2 = 508239242281 = 171676|171676|1 in base 9.
%t A071135 psq[b_, nd_] := Block[{sq={}, r, x}, Do[r = Mod[nd, p]; Do[x = (b^( Floor[nd/p] p) - 1)/(b^p - 1) t b^r + Floor[t/b^(p - r)]; If[ IntegerQ@ Sqrt@ x, AppendTo[ sq, x]], {t, b^(p - 1), b^p - 1}], {p, nd/2}]; sq]; Union @@ (psq[9, #] & /@ Range[10]) (* _Giovanni Resta_, Aug 01 2018 *)
%Y A071135 Cf. A071128 (base 2) - A071134 (base 8), A069919 (base 10).
%K A071135 base,nonn
%O A071135 1,1
%A A071135 _Erich Friedman_, May 28 2002
%E A071135 a(5)-a(12) from _Giovanni Resta_, Aug 01 2018