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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
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| 1843=19*97 is brilliant and 3481=59^2 is a square.
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MATHEMATICA
| 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[#]]]]]&] (* From Harvey P. Dale, Feb 06 2011 *)
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CROSSREFS
| Cf. A078972, A115667, A115669.
Sequence in context: A115710 A082749 A115675 * A000974 A035233 A010396
Adjacent sequences: A115665 A115666 A115667 * A115669 A115670 A115671
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KEYWORD
| nonn,base
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AUTHOR
| Giovanni Resta (g.resta(AT)iit.cnr.it), Jan 31 2006
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