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%I #25 Jun 24 2023 07:47:44
%S 1,2,3,4,5,6,7,8,9,36,51,66,81,102,123,144,225,258,291,324,363,402,
%T 441,576,593,610,627,644,661,678,695,712,729,748,767,786,805,824,843,
%U 862,881,900,1089,1158,1227,1296,1371,1446,1521,1764,1851,1938,2025
%N Indices of Wonderful Demlo numbers A002477 whose digit sums are squares.
%C The numbers 9*n^2 (A016766), with n > 0, are in this sequence. - _Enrique Pérez Herrero_, Sep 26 2020
%H Jeppe Stig Nielsen, <a href="/A080161/b080161.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/DemloNumber.html">Demlo Number</a>
%t A080151[n_] := (9^2)*(n/9 - FractionalPart[n/9] + FractionalPart[n/9]^2)
%t Select[Range[10000], IntegerQ[Sqrt[A080151[#]]] &]
%t (* _Enrique Pérez Herrero_, Sep 26 2020 *)
%o (PARI) for(k=1,10^5,issquare((k\9)*81+(k%9)^2)&&print1(k,", ")) \\ _Jeppe Stig Nielsen_, May 27 2023
%Y Cf. A080160, A080162, A002477, A080151, A108690.
%K nonn,base
%O 1,2
%A _Eric W. Weisstein_, Jan 31 2003
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