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%I #14 Jun 21 2017 22:04:26
%S 1,2,4,8,16,32,64,128,256,512,1024,2048,4096,8191,16382,32764,65528,
%T 131056,262112,524224,1048448,2096896,4193792,8387584,16775168,
%U 33550336
%N Divisors of 33550336, the 5th perfect number.
%C 8191 is the 5th Mersenne prime: A000668.
%C The number of divisors of the 5th perfect number is 2*A000043(5)=A061645(5)=26.
%C For the structure of this sequence and its binary expansion, see A135655.
%H <a href="/index/Di#divisors">Index entries for sequences related to divisors of numbers</a>
%H Omar E. Pol, <a href="http://www.polrpimos.com">Determinacion geometrica de los numeros primos y perfectos</a>.
%F 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).
%t Divisors[33550336] (* _Harvey P. Dale_, Jan 24 2015 *)
%o (PARI) divisors(33550336) \\ _Charles R Greathouse IV_, Jun 21 2017
%Y Cf. A018254, A018487. Perfect numbers: A000396.
%Y Cf. A000043, A000079, A000668, A061645, A133033, A135655.
%K fini,full,nonn,easy
%O 1,2
%A _Omar E. Pol_, Oct 26 2007, Mar 03 2008, Dec 27 2008
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