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A115668
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Brilliant numbers (A078972) whose digit reversal is a square.
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2
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4, 9, 10, 121, 169, 961, 1273, 1843, 10201, 10609, 12769, 16171, 44521, 48361, 48613, 94249, 96721, 106009, 108853, 121879, 129307, 445051, 526567, 613927, 1026169, 1042441, 1062961, 1216609, 1442401, 1692601
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OFFSET
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1,1
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LINKS
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EXAMPLE
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1843=19*97 is brilliant and 3481=59^2 is a square.
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MATHEMATICA
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brilQ[n_]:=Module[{fin=FactorInteger[n]}, Total[Transpose[fin][[2]]]==2&& Length[Union[IntegerLength[Transpose[fin][[1]]]]]==1]
brilnos=Select[Range[1700000], brilQ];
Select[brilnos, IntegerQ[Sqrt[FromDigits[Reverse[IntegerDigits[#]]]]]&] (* Harvey P. Dale, Feb 06 2011 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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