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A118072
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Primes which are the sum of a twin prime pair - 1.
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4
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7, 11, 23, 59, 83, 359, 383, 479, 563, 839, 863, 1283, 1319, 1619, 2039, 2063, 2099, 2459, 2579, 2903, 2963, 3863, 4259, 4283, 4679, 5099, 5939, 6599, 6659, 6719, 6779, 7079, 7643, 7703, 8039, 8543, 8963, 10463, 10559, 10883, 11003, 11279, 11483, 11699, 12263
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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EXAMPLE
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a(1) = 7 = 3 + 5 - 1 where (3,5) is a twin prime pair.
a(2) = 11 = 5 + 7 - 1 where (5,7) is a twin prime pair.
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MATHEMATICA
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Select[(Total[#]-1)&/@Select[Partition[Prime[Range[500]], 2, 1], Last[#]- First[#]== 2&], PrimeQ] (* Harvey P. Dale, Apr 04 2011 *)
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PROG
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(Magma) [p: p in PrimesUpTo(13000)|IsPrime((p-1) div 2) and IsPrime((p+3) div 2)]; // Marius A. Burtea, Jan 01 2020
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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