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A066242
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The floor((log(x))^2)-perfect numbers, where f-perfect numbers for an arithmetical function f are defined in A066218.
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0
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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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Let f(n) = floor((log(x))^2). Then f(18) = 8 = 4+3+1+0+0 = f(9)+f(6)+f(3)f(2)+f(1); so 18 is a term of the sequence.
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MATHEMATICA
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f[x_ ] := Floor[Log[x]^2]; Select[ Range[2, 10^5], 2 * f[ # ] == Apply[ Plus, Map[ f, Divisors[ # ] ] ] & ]
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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