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A109727
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Number of admirable numbers < 10^n.
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0
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OFFSET
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1,2
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LINKS
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Table of n, a(n) for n=1..10.
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MATHEMATICA
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fQ[n_] := Block[{d = Most[Divisors[n]], k = 1}, l = Length[d]; s = Plus @@ d; While[k < l && s - 2d[[k]] > n, k++ ]; If[k > l || s != n + 2d[[k]], False, True]]; c = 0; k = 1; Do[ While[k <= 10^n, If[ fQ[k], c++ ]; k++ ]; k++; Print[c], {n, 7}] (* Robert G. Wilson v *)
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CROSSREFS
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Cf. A111592.
Sequence in context: A147067 A147075 A268777 * A041320 A058380 A129746
Adjacent sequences: A109724 A109725 A109726 * A109728 A109729 A109730
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KEYWORD
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nonn
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AUTHOR
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Jason Earls, Aug 10 2005
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EXTENSIONS
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a(7) from Robert G. Wilson v, Aug 13 2005
a(8)-a(10) from Donovan Johnson, Jan 25 2012
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STATUS
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approved
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