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A224691
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Numbers n such that (13^n - 4^n)/9 is prime.
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1
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OFFSET
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1,1
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COMMENTS
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All terms are prime.
a(9) > 10^5.
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LINKS
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Table of n, a(n) for n=1..8.
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MATHEMATICA
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Select[Prime[Range[1, 100000]], PrimeQ[(13^# - 4^#)/9]&]
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PROG
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(PARI) is(n)=ispseudoprime((13^n-4^n)/9) \\ Charles R Greathouse IV, Jun 13 2017
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CROSSREFS
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Cf. A004063, A028491, A057468, A059801, A121877, A128024, A128025, A128026, A128027, A128028, A128029, A128030, A128031, A128032, A210506, A128347.
Sequence in context: A211207 A107882 A328977 * A192445 A089126 A113346
Adjacent sequences: A224688 A224689 A224690 * A224692 A224693 A224694
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KEYWORD
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nonn,hard,more
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AUTHOR
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Robert Price, Apr 15 2013
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STATUS
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approved
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