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A128447
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Numbers k such that absolute value of 7^k - k^7 is prime.
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9
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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PROG
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CROSSREFS
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Cf. A072180, A109387, A117705, A117706, A128448, A128449, A128450, A128451, A122003, A128453, A128454.
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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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