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A080160
Squares that are digit sums of Wonderful Demlo numbers A002477.
5
1, 4, 9, 16, 25, 36, 49, 64, 81, 324, 441, 576, 729, 900, 1089, 1296, 2025, 2304, 2601, 2916, 3249, 3600, 3969, 5184, 5329, 5476, 5625, 5776, 5929, 6084, 6241, 6400, 6561, 6724, 6889, 7056, 7225, 7396, 7569, 7744, 7921, 8100, 9801, 10404, 11025, 11664
OFFSET
1,2
COMMENTS
These are the squares in A080151.
LINKS
Eric Weisstein's World of Mathematics, Demlo Number
MAPLE
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
MATHEMATICA
A080151[n_] := (9^2)*(n/9 - FractionalPart[n/9] + FractionalPart[n/9]^2)
A080151[Select[Range[10000], IntegerQ[Sqrt[A080151[#]]] &]]
(* Enrique Pérez Herrero, Nov 05 2022 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Jun 19 2005
EXTENSIONS
More terms from Emeric Deutsch, Jun 19 2005
STATUS
approved