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A105549
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Numbers n such that 2*prime(n)+/-n are primes.
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1
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1, 3, 15, 27, 33, 45, 81, 189, 213, 243, 249, 279, 285, 291, 381, 423, 567, 615, 675, 687, 705, 813, 819, 1023, 1071, 1077, 1137, 1173, 1347, 1425, 1431, 1503, 1737, 1779, 1785, 1815, 1857, 1989, 1995, 2049, 2067, 2163, 2241, 2373, 2565, 2841
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OFFSET
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1,2
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LINKS
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MATHEMATICA
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bb={}; Do[If[PrimeQ[2 Prime[n]+n]&&PrimeQ[2 Prime[n]-n], bb=Append[bb, n]], {n, 1, 3000, 2}]; bb
Select[Range[3000], And@@PrimeQ[2Prime[#]+{#, -#}]&] (* Harvey P. Dale, Apr 07 2013 *)
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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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