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A265486
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Numbers n such that 64^n - 8^n - 1 is prime.
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1
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3, 6, 15, 19, 36, 75, 80, 118, 199, 336, 360, 520, 1282, 1810, 2872, 4870, 14467, 15102, 22499, 24675, 45615, 105648, 116432
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OFFSET
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1,1
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COMMENTS
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For n = 3, 6, 15, 19 the corresponding primes are 261631, 68719214591, 1237940039285345090527035391, 20769187434139310370006797241024511.
3*a(n) belongs to A098845 (the terms from a(18) to a(23) are derived from that sequence).
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LINKS
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EXAMPLE
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3 is in the sequence because 64^3 - 8^3 - 1 = 261631 is prime.
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MATHEMATICA
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Select[Range[1000], PrimeQ[64^# - 8^# - 1] &]
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PROG
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(Magma) [n: n in [0..300] | IsPrime(64^n-8^n-1)];
(PARI) for(n=1, 1e3, if(ispseudoprime(64^n - 8^n - 1), print1(n, ", "))) \\ Altug Alkan, Dec 12 2015
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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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