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%I A046762
%S A046762 1,10,60,65,84,130,140,150,175,260,350,420,525,780,1050,1105,1820,2100,
%T A046762 2210,4420,4650,5425,5460,8840,10500,10850,13260,16275,19720,20150,
%U A046762 20737,21700,30225,30940,32045,32550,41474,45500,55250,57350,60450
%N A046762 Sum of the squares of the divisors of n is divisible by n.
%C A046762 Compare with multiply perfect numbers A007691. Here Sum[ divisors ] is 
               replaced by Sum[ square of divisors ].
%C A046762 Problem 11090 proves that this sequence is infinite. - T. D. Noe (noe(AT)sspectra.com), 
               Apr 18 2006
%D A046762 Florian Luca, Problem 11090: Sometimes n divides sigma_k(n), Amer. Math. 
               Monthly 113 (2006), 372-373.
%H A046762 T. D. Noe, <a href="b046762.txt">Table of n, a(n) for n=1..1000</a>
%e A046762 n=65=a[ 4 ], sigma[ 2,65 ]=4420=65*68=68*n or n=1820=a[ 17 ], the divisor-square 
               sum is 4641000=2550*1820=2880*n
%Y A046762 A007691.
%Y A046762 Sequence in context: A054489 A140890 A055714 this_sequence A066290 A065641 
               A121874
%Y A046762 Adjacent sequences: A046759 A046760 A046761 this_sequence A046763 A046764 
               A046765
%K A046762 nonn
%O A046762 1,2
%A A046762 Labos E. (labos(AT)ana.sote.hu)

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


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