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%I A114887
%S A114887 120,672,32760,2178540,1379454720,14182439040,518666803200,
%T A114887 30823866178560,71065075104190073088,154345556085770649600,
%U A114887 9186050031556349952000,680489641226538823680000
%N A114887 Multiperfect numbers sigma(n)=k*n, which are divisible by the sum of 
               their prime factors without repetition.
%C A114887 From a list of about 5000 multiperfect numbers, 38 numbers were found 
               with the property, all having k<=9, the largest was the only one 
               having k=9. A091443 uses sofpr with repetition. Conjecture: the sequence 
               is finite.
%H A114887 Sven Simon, <a href="b114887.txt">Table of n, a(n) for n = 1..38</a> 
               [Conjectured to be complete]
%H A114887 Achim Flammenkamp, <a href="http://wwwhomes.uni-bielefeld.de/achim/mpn.html">
               List with multiperfect numbers</a>
%H A114887 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               MultiperfectNumber.html">Multiperfect numbers</a>
%e A114887 a(0) = 120 = 2^3*3*5, sofpr(120) = 2+3+5 = 10.
%Y A114887 Cf. A091443.
%Y A114887 Sequence in context: A090216 A113546 A166069 this_sequence A069085 A039688 
               A005820
%Y A114887 Adjacent sequences: A114884 A114885 A114886 this_sequence A114888 A114889 
               A114890
%K A114887 fini,nonn
%O A114887 1,1
%A A114887 Sven Simon (sven-h.simon(AT)t-online.de), Feb 19 2006

    
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Last modified November 29 12:46 EST 2009. Contains 167659 sequences.


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