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A363375
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Numbers k such that 3^(k-1) - 2^k is prime.
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1
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4, 6, 7, 8, 22, 32, 45, 52, 58, 60, 85, 98, 211, 290, 291, 426, 428, 712, 903, 1392, 1683, 1828, 2342, 3482, 4818, 4887, 9060, 14328, 16948, 17581, 18358, 65298, 69237, 84770, 94788
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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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a(1) = 4 is in the sequence because 3^3 - 2^4 = 11 is prime.
a(2) = 6 is in the sequence because 3^5 - 2^6 = 179 is prime.
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MATHEMATICA
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Cases[Range[1, 300], k_ /; PrimeQ[3^(k - 1) - 2^k]]
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CROSSREFS
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The sequence that results from increasing all terms by 1 in A162714 is a subsequence.
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KEYWORD
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nonn,hard,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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