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A138699
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Numbers k such that 4^k - 3^k - 2^k is prime.
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8
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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4^2 - 3^2 - 2^2 = 16 - 9 - 4 = 3.
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MAPLE
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MATHEMATICA
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Select[Range[11^3], PrimeQ[4^# - 3^# - 2^# ]&]
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PROG
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(PARI) for(n=1, 7500, if(ispseudoprime(4^n - 3^n - 2^n), print1(n, ", "))) \\ Derek Orr, Apr 08 2014
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CROSSREFS
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KEYWORD
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nonn,more,hard
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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