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A158709
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Primes p such that p + ceiling(p/2) is prime.
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15
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2, 3, 7, 11, 19, 31, 47, 59, 67, 71, 127, 131, 151, 167, 179, 211, 239, 307, 311, 347, 379, 431, 439, 467, 479, 547, 571, 587, 607, 619, 631, 647, 727, 739, 787, 811, 839, 859, 907, 911, 967, 991, 1039, 1091, 1231, 1259, 1319, 1399, 1427, 1471, 1511, 1531, 1559
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OFFSET
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1,1
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COMMENTS
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Or, 2 along with primes p such that Sum_{x=1..p} (1 - (-1)^x*x) is prime. - Juri-Stepan Gerasimov, Jul 14 2009
Apart from the first term, primes of the form 4*k-1 such that 6*k-1 is also prime. - Charles R Greathouse IV, Nov 09 2011
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LINKS
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MATHEMATICA
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lst={}; Do[p=Prime[n]; If[PrimeQ[Ceiling[p/2]+p], AppendTo[lst, p]], {n, 6!}]; lst
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PROG
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(PARI) print1(2); forprime(p=3, 1e4, if(p%4==3&&isprime(p\4*6+5), print1(", "p))) \\ Charles R Greathouse IV, Nov 09 2011
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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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