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A063784 Primes that are the sum of cubes of divisors of an integer. 2

%I

%S 73,757,1772893,48551233240513,378890487846991,3156404483062657,

%T 17390284913300671,280343912759041771,319913861581383373,

%U 487014306953858713,7824668707707203971,8443914727229480773

%N Primes that are the sum of cubes of divisors of an integer.

%H Harry J. Smith, <a href="/A063784/b063784.txt">Table of n, a(n) for n = 1..1000</a>

%F Primes of form p = sigma(3, x).

%e sigma(3,9) = 1 + 27 + 729 = 757, a prime.

%o (PARI) { n=0; p=0; for (m=1, 10^9, p=nextprime(p+1); if(isprime(q=p^6 + p^3 + 1), write("b063784.txt", n++, " ", q); if (n==1000, break)) ) } \\ _Harry J. Smith_, Aug 31 2009

%Y Cf. A001158, A023194.

%K nonn

%O 1,1

%A _Labos Elemer_, Aug 17 2001

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Last modified November 14 00:05 EST 2019. Contains 329106 sequences. (Running on oeis4.)