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 A060678 Numbers n such that sigma (x) = n has exactly 11 solutions. 0
 576, 1296, 2976, 3168, 3648, 3720, 4788, 4896, 5544, 6300, 9000, 9840, 10656, 11808, 12528, 13020, 13320, 14760, 15456, 16740, 17920, 18288, 18576, 19344, 19840, 20400, 21280, 22800, 23296, 24300, 26712, 26928, 27552, 27936, 28392 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE 576 = sigma(210) = sigma(282) = sigma(310) = sigma(322) = sigma(345) = sigma(357) = sigma(382) = sigma(385) = sigma(497) = sigma(517) = sigma(527). MATHEMATICA a = Table[ 0, {30000} ]; Do[ s = DivisorSigma[ 1, n ]; If[ s < 30001, a[ [ s ] ]++ ], {n, 1, 30000} ]; Select[ Range[ 30000 ], a[ [ # ] ] == 11 & ] CROSSREFS Cf. A007370, A007371, A007372. Sequence in context: A258919 A064253 A069266 * A254848 A235181 A268773 Adjacent sequences:  A060675 A060676 A060677 * A060679 A060680 A060681 KEYWORD nonn AUTHOR Robert G. Wilson v, Apr 18 2001 STATUS approved

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Last modified May 27 09:28 EDT 2022. Contains 354096 sequences. (Running on oeis4.)