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A091180
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Primes of the form 3*p - 2 such that p is a prime.
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32
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7, 13, 19, 31, 37, 67, 109, 127, 139, 157, 181, 199, 211, 307, 337, 379, 409, 487, 499, 541, 571, 577, 631, 751, 769, 787, 811, 829, 877, 919, 937, 991, 1009, 1039, 1117, 1201, 1291, 1297, 1327, 1381, 1399, 1459, 1471, 1567, 1621, 1669, 1759, 1777, 1801
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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(4) = 31: 3*11 - 2 = 31; A088878(4) = 11.
a(6) = 67: 3*23 - 2 = 67; A088878(6) = 23.
(End)
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MAPLE
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MATHEMATICA
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n = 1; a = {}; Do[If[PrimeQ[(Prime[k] + 2n)/(2n + 1)], AppendTo[a, Prime[k]]], {k, 1, 500}]; a (* Artur Jasinski, Dec 12 2007 *)
Select[Table[3*Prime[n] - 2, {n, 1000}], PrimeQ] (* K. D. Bajpai, Jun 20 2015 *)
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PROG
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(PARI) forprime(p = 1, 1000, k =( 3*p -2); if ( isprime(k), print1(k, ", "))); \\ K. D. Bajpai, Jun 20 2015
(Magma) [ k: p in PrimesUpTo(1000) | IsPrime(k) where k is (3*p-2) ]; // K. D. Bajpai, Jun 20 2015
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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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