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A138656
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Primes p such that 42*p - 1 and 42*p + 1 are twin primes.
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3
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11, 31, 41, 101, 131, 211, 239, 331, 419, 421, 509, 619, 691, 751, 769, 1091, 1129, 1279, 1531, 1571, 1609, 1901, 2111, 2221, 2251, 2281, 2341, 2699, 2719, 2879, 2971, 3221, 3541, 3671, 3821, 3851, 4271, 4349, 4421, 4519, 4561, 4651, 4861, 4909, 4969
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OFFSET
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1,1
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LINKS
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EXAMPLE
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11 is a term since it is a prime and 42*11 - 1 = 461 and 42*11 + 1 = 463 are twin primes.
31 is a term since it is a prime and 42*31 - 1 = 1301 and 42*31 + 1 = 1303 are twin primes.
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MATHEMATICA
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a=42; Select[Prime[Range[10^3]], PrimeQ[a*#-1]&&PrimeQ[a*#+1]&]
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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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