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%I #2 Mar 30 2012 17:30:31
%S 504,864,960,1152,1260,2400,3276,3888,4992,6696,7020,7644,8892,9672,
%T 9984,11172,11200,11376,11616,11856,12936,13728,13888,14136,14280,
%U 15480,15876,15984,17808,19488,21336,22608,23688,24738,24840,25080
%N Sigma(x) = n has exactly ten solutions.
%e 504 = sigma(204) = sigma(220) = sigma(224) = sigma(246) = sigma(284) = sigma(286) = sigma(334) = sigma(415) = sigma(451) = sigma(504).
%t a = Table[ 0, {30000} ]; Do[ s = DivisorSigma[ 1, n ]; If[ s < 30001, a[ [ s ] ]++ ], {n, 1, 30000} ]; Select[ Range[ 30000 ], a[ [ # ] ] == 10 & ]
%Y Cf. A007370, A007371, A007372.
%K nonn
%O 1,1
%A _Robert G. Wilson v_, Apr 18 2001
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