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A270104 Numbers n such that 3^n + n*2^n is prime. 1
1, 2, 7, 8, 13, 43, 55, 59, 145, 149, 545, 2468, 4049, 4055, 15653, 22765 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
a(17) > 30000. - Giovanni Resta, May 05 2016
LINKS
EXAMPLE
n = 2 is a term since 3^2 + 2*2^2 = 17 is prime.
MATHEMATICA
Select[Range[1000], PrimeQ[3^# + # * 2^#]&] (* Giovanni Resta, May 05 2016 *)
PROG
(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
CROSSREFS
Sequence in context: A004717 A308918 A226819 * A063531 A063771 A064293
KEYWORD
nonn,more
AUTHOR
Vardan Semerjyan, Mar 11 2016
EXTENSIONS
a(15)-a(16) from Giovanni Resta, May 05 2016
STATUS
approved

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Last modified March 29 10:44 EDT 2024. Contains 371268 sequences. (Running on oeis4.)