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A178507
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Numbers n that (n^3 - 4,n^3 - 2) is a twin prime pair.
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1
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15, 201, 411, 477, 561, 1065, 1335, 1515, 1527, 1617, 2001, 2331, 2355, 2511, 2517, 2637, 2727, 2817, 3117, 3927, 4131, 4611, 4755, 4797, 5121, 5427, 5457, 5787, 6045, 6501, 6675, 7347, 7395, 8637, 9591, 9711, 10071, 10305, 10371, 10377, 10965, 11031
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OFFSET
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1,1
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COMMENTS
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Necessarily n odd multiple of 3, LSD of n is e = 1, 5 or 7.
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LINKS
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EXAMPLE
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p = 15^3 - 4 = 3371 = prime(475), p+2 = prime(476), 15 is first term.
p = 201^3 - 4 = 8120597 = prime(547310), p+2 = prime(547311), 201 is 2nd term.
p = 15915^3 - 4 = 4031066185871 = prime(i), i = 144036640497, p+2 = prime(i+1), 15915 is another term.
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MATHEMATICA
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Select[Range[12000], AllTrue[#^3-{4, 2}, PrimeQ]&] (* Harvey P. Dale, Jul 28 2024 *)
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PROG
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(PARI) is(n) = isprime(n^3-2) && isprime(n^3-4) \\ Michel Marcus, Jul 22 2013
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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Ulrich Krug (leuchtfeuer37(AT)gmx.de), May 29 2010
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EXTENSIONS
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STATUS
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approved
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