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A175172
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Primes p such that 3*2^p+1 is also prime.
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2
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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=2, 3*2^2+1=13; p=5. 3*2^5+1=97; p=41, 3*2^41+1=6597069766657.
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MAPLE
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select(p->isprime(p) and isprime(3*2^p+1), [$0..5000]); # Muniru A Asiru, Dec 19 2018
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MATHEMATICA
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PROG
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(Magma) [p: p in PrimesUpTo(4000) | IsPrime(3*2^p+1)]
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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