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A103803
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Primes p such that both 2p - 15 and 2p + 15 are primes.
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5
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11, 13, 19, 23, 29, 37, 41, 43, 47, 61, 71, 83, 89, 107, 113, 127, 139, 149, 191, 197, 223, 281, 293, 331, 379, 419, 421, 461, 463, 491, 499, 503, 523, 569, 593, 601, 653, 719, 733, 769, 797, 811, 821, 839, 881, 887, 1049, 1063, 1129, 1163, 1181, 1213, 1231
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OFFSET
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1,1
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LINKS
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FORMULA
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p, 2p-15 and 2p+15 all are positive and are primes (hence we omit p=2).
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MATHEMATICA
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Select[Range[11, 2000], PrimeQ[ # ] && PrimeQ[2# + 15] && PrimeQ[2# - 15] &]
Select[Prime[Range[2, 250]], And@@PrimeQ[2#+{15, -15}]&] (* Harvey P. Dale, May 21 2013 *)
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PROG
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(Magma) [p: p in PrimesUpTo(3200)| IsPrime(2*p+15) and IsPrime(2*p-15) ]; // Vincenzo Librandi, Jan 28 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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