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A060666
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Sigma(x) = n has exactly ten solutions.
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0
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504, 864, 960, 1152, 1260, 2400, 3276, 3888, 4992, 6696, 7020, 7644, 8892, 9672, 9984, 11172, 11200, 11376, 11616, 11856, 12936, 13728, 13888, 14136, 14280, 15480, 15876, 15984, 17808, 19488, 21336, 22608, 23688, 24738, 24840, 25080
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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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504 = sigma(204) = sigma(220) = sigma(224) = sigma(246) = sigma(284) = sigma(286) = sigma(334) = sigma(415) = sigma(451) = sigma(504).
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MATHEMATICA
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a = Table[ 0, {30000} ]; Do[ s = DivisorSigma[ 1, n ]; If[ s < 30001, a[ [ s ] ]++ ], {n, 1, 30000} ]; Select[ Range[ 30000 ], a[ [ # ] ] == 10 & ]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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