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A270104
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Numbers n such that 3^n + n*2^n is prime.
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1
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1, 2, 7, 8, 13, 43, 55, 59, 145, 149, 545, 2468, 4049, 4055, 15653, 22765
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OFFSET
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1,2
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COMMENTS
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a(17) > 30000. - Giovanni Resta, May 05 2016
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LINKS
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Table of n, a(n) for n=1..16.
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EXAMPLE
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n = 2 is a term since 3^2 + 2*2^2 = 17 is prime.
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MATHEMATICA
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Select[Range[1000], PrimeQ[3^# + # * 2^#]&] (* Giovanni Resta, May 05 2016 *)
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PROG
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(MATLAB)
if isprime(3^n + n*2^n)
disp(n)
end
(PARI) is(n)=ispseudoprime(3^n+n*2^n) \\ Charles R Greathouse IV, Jun 13 2017
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CROSSREFS
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Cf. A270102, A123924.
Sequence in context: A004717 A308918 A226819 * A063531 A063771 A064293
Adjacent sequences: A270101 A270102 A270103 * A270105 A270106 A270107
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KEYWORD
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nonn,more
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AUTHOR
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Vardan Semerjyan, Mar 11 2016
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EXTENSIONS
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a(15)-a(16) from Giovanni Resta, May 05 2016
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STATUS
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approved
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