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A106630
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Numbers k such that (prime(k)^2 - 1)/6 - prime(k) is prime.
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1
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7, 8, 12, 13, 17, 20, 24, 25, 28, 29, 32, 39, 42, 45, 52, 53, 58, 59, 63, 64, 67, 72, 75, 79, 83, 87, 88, 93, 100, 102, 114, 115, 125, 126, 127, 131, 139, 140, 144, 154, 159, 160, 173, 180, 190, 195, 219, 223, 232, 234, 240, 248, 253, 265, 278, 279, 284, 296, 299
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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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(17^2 -1)/6 - 17 = 48 - 17 = 31 is prime, 17=prime(7), so 7 is a term.
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MATHEMATICA
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Select[Range[350], PrimeQ[(Prime[#]^2 -6*Prime[#] -1)/6] &] (* G. C. Greubel, Sep 08 2021 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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