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A153133 Primes of the form 2^n+3^(n-1). 1
3, 7, 17, 43, 113, 307, 857, 20707, 181243, 539633, 14414443, 129402307, 31389448217, 1853028778786433, 5559077746424707, 50031613818476443, 150094772735952593, 8862938260389989451257, 26588814640432479998443 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..37

MATHEMATICA

lst={}; Do[p=2^n+3^(n-1); If[PrimeQ[p], AppendTo[lst, p]], {n, 0, 5!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Jun 15 2009]

PROG

(MAGMA) [a: n in [0..100] | IsPrime(a) where a is 2^n+3^(n-1)];

CROSSREFS

Cf. A082400.

Sequence in context: A078679 A025577 A085279 * A123601 A115325 A018025

Adjacent sequences:  A153130 A153131 A153132 * A153134 A153135 A153136

KEYWORD

nonn

AUTHOR

Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Mar 11 2009

EXTENSIONS

Added more terms and Mathematica program. Vladimir Orlovsky (4vladimir(AT)gmail.com), Jun 15 2009

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Last modified February 16 04:18 EST 2012. Contains 205860 sequences.