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Search: id:A057809
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%I A057809
%S A057809 2,4,6,8,27,30,33,96,100,120,330,335,340,350,355,360,1008,1080,1092,
%T A057809 1116,1122,1128,1134,3059,3066,3073,3080,3087,3094,8408,8424,8440,8456,
%U A057809 8464,8472,23526,23535,24300,64540,64580,64610,64620,64650,64690,64700
%N A057809 Numbers n such that pi(n) divides n.
%C A057809 Each cluster of entries is approximately a power of e from the previous 
               cluster.
%e A057809 120 is a member as there are exactly 30 primes less than 120 and 30*4 
               = 120.
%t A057809 Select[ Range[2, 10^5], IntegerQ[ # / PrimePi[ # ]] & ]
%Y A057809 Cf. A000720, A057810, A071394, A038627. Apart from initial term same 
               as A058011.
%Y A057809 Sequence in context: A067732 A117912 A092047 this_sequence A135632 A068541 
               A108425
%Y A057809 Adjacent sequences: A057806 A057807 A057808 this_sequence A057810 A057811 
               A057812
%K A057809 nonn
%O A057809 1,1
%A A057809 N. J. A. Sloane (njas(AT)research.att.com), Nov 07 2000
%E A057809 More terms from James A. Sellers (sellersj(AT)math.psu.edu), Nov 08 2000

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


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