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A172976
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Primes p such that 2p - 1 and 6p - 1 are prime.
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1
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2, 3, 7, 19, 157, 199, 229, 379, 439, 577, 829, 877, 967, 997, 1009, 1279, 1429, 1459, 1657, 2137, 2539, 3067, 3169, 3187, 3319, 3739, 3769, 3967, 4159, 4357, 4447, 4909, 4987, 6079, 6379, 6427, 6709, 6967, 7219, 7297, 7639, 8209, 9049, 9067, 9157, 9277
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OFFSET
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1,1
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LINKS
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Iain Fox, Table of n, a(n) for n = 1..10000
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PROG
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(Magma) [p: p in PrimesUpTo(10000)|IsPrime(2*p-1) and IsPrime(6*p-1)] // Vincenzo Librandi, Jan 29 2011
(PARI) lista(nn) = forprime(p=2, nn, if(isprime(2*p - 1) && isprime(6*p - 1), print1(p, ", "))) \\ Iain Fox, Jan 20 2018
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CROSSREFS
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Sequence in context: A075487 A110498 A244917 * A171655 A293683 A006073
Adjacent sequences: A172973 A172974 A172975 * A172977 A172978 A172979
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KEYWORD
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nonn,easy,less
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AUTHOR
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Juri-Stepan Gerasimov, Feb 06 2010
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EXTENSIONS
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Corrected and extended by Charles R Greathouse IV, Mar 25 2010
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STATUS
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approved
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