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Numbers n such that n + 15, n^2 + 15, n^3 + 15, n^4 + 15, n^5 + 15 and n^6 + 15 are all prime.
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%I #38 Mar 14 2016 10:06:41

%S 2,4,10830278,11409622,37189336,41206834,44438468,65401492,67135342,

%T 85329104,92243452,110149004,138651242,182279216,205680028,216904744,

%U 307575212,309431906,469311346,490359076,527228606,529432582,549804952,572599934,575037022,596410214,599921326,616509454,643063226,679784492,681657946,722166524,736641808,766101998,789147538,824154506,857134166,870601984,878365744,914746816

%N Numbers n such that n + 15, n^2 + 15, n^3 + 15, n^4 + 15, n^5 + 15 and n^6 + 15 are all prime.

%H Zak Seidov, <a href="/A252783/b252783.txt">Table of n, a(n) for n = 1..157</a>

%e 15 + {2, 4, 8, 16, 32, 64} = {17, 19, 23, 31, 47, 79} all primes.

%o (PARI) isok(n) = isprime(n+15) && isprime(n^2 + 15) && isprime(n^3 + 15) && isprime(n^4 + 15) && isprime(n^5 + 15) && isprime(n^6 + 15); \\ _Michel Marcus_, Dec 28 2014

%Y Cf. A253166, A253143, A253142, A086303, A121982.

%K nonn

%O 1,1

%A _Zak Seidov_, Dec 27 2014