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A122721
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Numbers n such that abs(7^n - 2^11) is prime.
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0
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2, 4, 5, 6, 9, 21, 41, 52, 58, 118, 130, 585, 614, 744, 881, 941, 966, 1280, 1658, 4985
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OFFSET
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1,1
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LINKS
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EXAMPLE
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For x = 2 abs(7^2-2^11) = 1999 which is prime. So 2 is the first entry.
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PROG
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(PARI) g(n) = for(x=1, n, y=abs(7^x-2^11); if(ispseudoprime(y), print1(x", ")))
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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