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Primes p such that p^8 - p^7 - p^6 - p^5 - p^4 - p^3 - p^2 - p - 1 is prime.
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%I #5 Jun 04 2014 15:01:55

%S 5,23,41,61,73,103,109,157,167,181,307,311,347,367,467,577,593,601,

%T 677,709,739,839,863,1039,1181,1201,1279,1381,1399,1621,1627,1789,

%U 1847,1861,1871,1913,1997,2063,2287,2347,2371,2657,2699,2797,2887,2963,3209,3343,3359,3623

%N Primes p such that p^8 - p^7 - p^6 - p^5 - p^4 - p^3 - p^2 - p - 1 is prime.

%e 5 is prime and 5^8 - 5^7 - 5^6 - 5^5 - 5^4 - 5^3 - 5^2 - 5 - 1 = 292969 is prime. Thus 5 is a member of this sequence.

%o (Python)

%o import sympy

%o from sympy import isprime

%o {print(n,end=', ') for n in range(10**4) if isprime(n**8-n**7-n**6-n**5-n**4-n**3-n**2-n-1) and isprime(n)}

%o (PARI) for(n=1,10^4,if(ispseudoprime(n)&&ispseudoprime(n^8-sum(i=0,7,n^i)),print1(n,", ")))

%Y Cf. A243297.

%K nonn

%O 1,1

%A _Derek Orr_, Jun 04 2014