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%I #5 Nov 21 2013 12:48:47
%S 4,9,10,121,169,961,1273,1843,10201,10609,12769,16171,44521,48361,
%T 48613,94249,96721,106009,108853,121879,129307,445051,526567,613927,
%U 1026169,1042441,1062961,1216609,1442401,1692601
%N Brilliant numbers (A078972) whose digit reversal is a square.
%e 1843=19*97 is brilliant and 3481=59^2 is a square.
%t brilQ[n_]:=Module[{fin=FactorInteger[n]},Total[Transpose[fin][[2]]]==2&& Length[Union[IntegerLength[Transpose[fin][[1]]]]]==1]
%t brilnos=Select[Range[1700000],brilQ];
%t Select[brilnos,IntegerQ[Sqrt[FromDigits[Reverse[IntegerDigits[#]]]]]&] (* _Harvey P. Dale_, Feb 06 2011 *)
%Y Cf. A078972, A115667, A115669.
%K nonn,base
%O 1,1
%A _Giovanni Resta_, Jan 31 2006
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