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A165566
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Primes p such that (p^2-1)/8-p is also prime.
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2
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17, 23, 31, 47, 73, 79, 103, 113, 127, 151, 167, 193, 199, 233, 241, 311, 313, 337, 401, 433, 479, 503, 521, 569, 577, 601, 631, 647, 719, 809, 823, 839, 863, 887, 911, 919, 953, 1031, 1049, 1087, 1129, 1151, 1193, 1201, 1217, 1231, 1249, 1303, 1433, 1439, 1487
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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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EXAMPLE
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For p=17, (17^2-1)/8-17=19 is prime, which adds p=17 to the sequence.
For p=23, (23^2-1)/8-23=43 is prime, which adds p=23 to the sequence.
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MATHEMATICA
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Select[Prime[Range[5, 1000]], PrimeQ[(#^2 - 1) / 8 - #]&] (* Vincenzo Librandi, Apr 10 2013 *)
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PROG
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(Magma) [p: p in PrimesInInterval(7, 1500) | IsPrime(((p^2-1) div 8) - p)]; // Vincenzo Librandi, Apr 10 2013
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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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EXTENSIONS
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STATUS
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approved
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