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A173906
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Total number of digits of the squares of all n-digit numbers.
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0
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16, 338, 5183, 69837, 878377, 10583772, 123837722, 1418377223, 15983772233, 177837722339, 1958377223398, 21383772233983, 231837722339831, 2498377223398316, 26783772233983162, 285837722339831620, 3038377223398316206, 32183772233983162066, 339837722339831620668, 3578377223398316206680
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OFFSET
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1,1
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COMMENTS
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Sequence inspired by Claudio Meller's email to [seqfan] 07:01 a.m., Nov 26 2010, subject: About a problem of Bernardo Recamán Santos found in http://www.mathpuzzle.com/
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LINKS
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FORMULA
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As n -> infinity, a(n)/(n*10^(n+floor(log(log(n))+1)) -> 9/50.
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MATHEMATICA
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f[n_] := Block[{br = 1+ Floor[10^(n-1)*Sqrt@10]}, (2n-1)(br-10^(n-1)) + 2n(10^n-br)]; Array[f, 20]
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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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