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A274693
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Numbers n such that 4^n + 3^(n+1) is prime.
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0
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1, 2, 4, 5, 9, 10, 12, 17, 18, 29, 30, 40, 58, 82, 113, 129, 164, 192, 252, 524, 624, 766, 977, 1742, 2208, 2440, 3052, 4742, 5480, 16572, 17501
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OFFSET
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1,2
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COMMENTS
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a(32) > 10^5.
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LINKS
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Table of n, a(n) for n=1..31.
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EXAMPLE
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5 is a member since 4^5 + 3^6 = 1024 + 729 = 1753 which is a prime number.
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MATHEMATICA
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Select[Range[0, 100000], PrimeQ[4^# + 3^(# + 1)] &]
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PROG
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(PARI) lista(nn) = for(n=1, nn, if(ispseudoprime(4^n + 3^(n+1)), print1(n, ", "))); \\ Altug Alkan, Jul 02 2016
(Magma) [n: n in [1..700] | IsPrime(4^n + 3^(n+1))]; // Vincenzo Librandi, Jul 03 2016
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CROSSREFS
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Cf. A093713, A082103, A093717, A093793, A096185, A093794, A093795, A096186, A271883.
Sequence in context: A036795 A307563 A289175 * A024618 A089221 A347877
Adjacent sequences: A274690 A274691 A274692 * A274694 A274695 A274696
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KEYWORD
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nonn,more
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AUTHOR
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Robert Price, Jul 02 2016
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STATUS
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approved
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