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A271884
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Numbers n such that 4^n-3^(n-1) is prime.
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6
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1, 2, 4, 6, 10, 12, 30, 42, 54, 166, 264, 886, 1476, 8412, 9576, 12426, 24076
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OFFSET
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1,2
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COMMENTS
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a(18) > 10^5.
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LINKS
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EXAMPLE
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4 is a member since 4^4 - 3^3 = 256 - 27 = 229 which is a prime number.
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MATHEMATICA
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Select[Range[0, 100000], PrimeQ[4^# - 3^(# - 1)] &]
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PROG
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(PARI) lista(nn) = for(n=1, nn, if(ispseudoprime(4^n-3^(n-1)), print1(n, ", "))); \\ Altug Alkan, Apr 16 2016
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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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