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%I A133025
%S A133025 1,2,4,8,16,32,64,128,256,512,1024,2048,4096,8191,16382,32764,65528,
%T A133025 131056,262112,524224,1048448,2096896,4193792,8387584,16775168,33550336
%N A133025 Divisors of 33550336, the 5th perfect number.
%C A133025 8191 is the 5th Mersenne prime: A000668.
%C A133025 The number of divisors of the 5th perfect number is 2*A000043(5)=A061645(5)=26.
%C A133025 For the structure of this sequence and its binary expansion, see A135655.
%H A133025 O. E. Pol, <a href="http://www.polrpimos.com">Determinacion geometrica 
               de los numeros primos y perfectos</a>.
%F A133025 For n=1..13 : a(n) = 2^(n-1). For n=14..26: a(n) = 2^(n-1) - 2^(n-14) 
               = A000668(5)*2^(n-14).
%Y A133025 Cf. A018254, A018487. Perfect numbers: A000396.
%Y A133025 Cf. A000043, A000079, A000668, A061645, A133033, A135655.
%Y A133025 Sequence in context: A056767 A008863 A145117 this_sequence A118655 A155559 
               A166687
%Y A133025 Adjacent sequences: A133022 A133023 A133024 this_sequence A133026 A133027 
               A133028
%K A133025 fini,full,nonn
%O A133025 1,2
%A A133025 Omar E. Pol (info(AT)polprimos.com), Oct 26 2007, Mar 03 2008, Dec 27 
               2008

    
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Last modified November 27 22:38 EST 2009. Contains 167602 sequences.


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