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A180737
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a(n) is the largest n-digit square whose sum of digits is also a square.
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2
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9, 81, 961, 9025, 96721, 990025, 9966649, 99980001, 999761161, 9999400009, 99998250625, 999946000729, 9999989500176, 99999960000004, 999999455981824, 9999998600000049, 99999998724439696, 999999998000000001
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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lnds[n_]:=Module[{s=Floor[Sqrt[10^n-1]]}, While[!IntegerQ[Sqrt[Total[ IntegerDigits[ s^2]]]], s--]; s^2]; Array[lnds, 20] (* Harvey P. Dale, Mar 28 2013 *)
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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