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A174367
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Primes p such that 2*p^4-+21 are also prime.
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1
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2, 197, 499, 587, 601, 1237, 2111, 2153, 2861, 3253, 3301, 3923, 4373, 5101, 5387, 5437, 6529, 6563, 7459, 9817, 9833, 10477, 11047, 11699, 12101, 12823, 12907, 13859, 14087, 15569, 21401, 21929, 22727, 23473, 23687, 23893, 25633, 26393
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OFFSET
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1,1
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LINKS
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EXAMPLE
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For p=2, 2*2^4-+21=(11,53); p=197, 2*197^4-+21=(3012276941,3012276983)
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MATHEMATICA
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Select[Prime[Range[1000]], And@@PrimeQ[2 #^4 + {21, -21}]&] (* Vincenzo Librandi, Apr 10 2013 *)
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PROG
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(Magma) [p: p in PrimesUpTo(100000)|IsPrime(2*p^4-21) and IsPrime(2*p^4+21)];
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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