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A153320
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Primes p such that p^2 - 48 and p^2 + 48 are also primes.
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4
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5, 17, 19, 59, 61, 191, 227, 521, 641, 683, 709, 857, 863, 919, 983, 1031, 1039, 1097, 1117, 1123, 1151, 1229, 1423, 1543, 1579, 1621, 1699, 1733, 1759, 1867, 1871, 2153, 2237, 2287, 2357, 2383, 2557, 2621, 2879, 2971, 3301, 3329, 3371, 3581, 3847, 4021
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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fQ[n_]:=PrimeQ[n^2-48]&&PrimeQ[n^2+48]; lst={}; Do[If[fQ@Prime[n], AppendTo[lst, Prime[n]]], {n, 7!}]; lst
Select[Prime[Range[PrimePi[4500]]], AllTrue[#^2+{48, -48}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Dec 08 2015 *)
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PROG
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(Magma) [p: p in PrimesUpTo(5000)|IsPrime(p^2-48) and IsPrime(p^2+48)] // Vincenzo Librandi, Jan 30 2011
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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