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A309726
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Numbers k such that k^2 - 12 is prime.
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1
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5, 7, 11, 13, 17, 19, 25, 29, 35, 41, 49, 53, 59, 61, 79, 85, 91, 95, 97, 103, 107, 113, 119, 121, 137, 139, 145, 149, 163, 169, 173, 179, 181, 185, 191, 205, 209, 227, 233, 235, 245, 251
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OFFSET
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1,1
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COMMENTS
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All terms are odd and not divisible by 3.
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LINKS
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FORMULA
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EXAMPLE
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11 is in the sequence because 11^2 - 12 = 109, which is prime.
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MATHEMATICA
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Select[Range[5, 301, 2], PrimeQ[#^2-12]&] (* Harvey P. Dale, Dec 23 2019 *)
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PROG
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(PARI) select(n->isprime(n^2-12), [1..1000]) \\ Andrew Howroyd, Aug 14 2019
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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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