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 A080160 #27 Jul 31 2025 08:41:19
%S A080160 1,4,9,16,25,36,49,64,81,324,441,576,729,900,1089,1296,2025,2304,2601,
%T A080160 2916,3249,3600,3969,5184,5329,5476,5625,5776,5929,6084,6241,6400,
%U A080160 6561,6724,6889,7056,7225,7396,7569,7744,7921,8100,9801,10404,11025,11664
%N A080160 Squares that are digit sums of Wonderful Demlo numbers A002477.
%C A080160 These are the squares in A080151.
%C A080160 x^2 is a term iff x mod 81 is in {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 18, 21, 24, 27, 30, 33, 36, 45, 48, 51, 54, 57, 60, 63, 72, 73, 74, 75, 76, 77, 78, 79, 80}. - _Robert Israel_, Jul 30 2025
%H A080160 Robert Israel, <a href="/A080160/b080160.txt">Table of n, a(n) for n = 1..10000</a>
%H A080160 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/DemloNumber.html">Demlo Number</a>
%p A080160 b:=n->sum(convert(((10^(n+1)-1)/9)^2,base,10)[j],j=1..2*n+1): a:=proc(n) if type(sqrt(b(n)),integer)=true then b(n) else fi end: seq(a(n),n=0..2000); # _Emeric Deutsch_, Jun 19 2005
%t A080160 A080151[n_] := (9^2)*(n/9 - FractionalPart[n/9] + FractionalPart[n/9]^2)
%t A080160 A080151[Select[Range[10000], IntegerQ[Sqrt[A080151[#]]] &]]
%t A080160 (* _Enrique Pérez Herrero_, Nov 05 2022 *)
%Y A080160 Cf. A002477, A080151, A080161, A080162.
%Y A080160 Cf. A007953.
%K A080160 nonn,base
%O A080160 1,2
%A A080160 _N. J. A. Sloane_, Jun 19 2005
%E A080160 More terms from _Emeric Deutsch_, Jun 19 2005