A080160 - OEIS

%I #21 Nov 13 2022 12:35:55

%S 1,4,9,16,25,36,49,64,81,324,441,576,729,900,1089,1296,2025,2304,2601,

%T 2916,3249,3600,3969,5184,5329,5476,5625,5776,5929,6084,6241,6400,

%U 6561,6724,6889,7056,7225,7396,7569,7744,7921,8100,9801,10404,11025,11664

%N Squares that are digit sums of Wonderful Demlo numbers A002477.

%C These are the squares in A080151.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/DemloNumber.html">Demlo Number</a>

%p 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 A080151[n_] := (9^2)*(n/9 - FractionalPart[n/9] + FractionalPart[n/9]^2)

%t A080151[Select[Range[10000], IntegerQ[Sqrt[A080151[#]]] &]]

%t (* _Enrique Pérez Herrero_, Nov 05 2022 *)

%Y Cf. A002477, A080151, A080161, A080162.

%Y Cf. A007953.

%K nonn,base

%O 1,2

%A _N. J. A. Sloane_, Jun 19 2005

%E More terms from _Emeric Deutsch_, Jun 19 2005