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%I A087004
%S A087004 60,120,180,504,720,11550,12180,17940,19380,21252,22230,26334,27846,
%T A087004 29172,32340,34440,34580,43470,48840,56430,59220,59670,63240,66120,
%U A087004 70686,82824,85140,91350,95700,95940,99528,112840,113220,113652,115368
%N A087004 Numbers whose number of divisors equals the sum of their separate prime-power 
               decompositions.
%D A087004 S. Kahan,"Divisor Advisory", Journal of Recreational Mathematics 30(1) 
               41-4 1999-2000 Baywood NY.
%e A087004 504=2^3*3^2*7 is in the sequence because d(504)=A000005(504)=(3+1)*(2+1)*(1+1)=24 
               = 2^3 + 3^2 + 7. Similarly for 32340=2^2*3*5*7^2*11, where d(32340) 
               = 2^2 + 3 + 5 + 7^2 + 11 = 72.
%Y A087004 Cf. A078511.
%Y A087004 Sequence in context: A056866 A098136 A060793 this_sequence A049058 A056501 
               A056491
%Y A087004 Adjacent sequences: A087001 A087002 A087003 this_sequence A087005 A087006 
               A087007
%K A087004 nonn
%O A087004 1,1
%A A087004 Lekraj Beedassy (blekraj(AT)yahoo.com), Oct 13 2003

    
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Last modified December 2 11:54 EST 2009. Contains 167921 sequences.


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