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A082103 Numbers n such that 3^n+2^(n-1) is prime. 9
2, 3, 4, 6, 7, 8, 10, 15, 21, 24, 36, 49, 51, 86, 116, 134, 176, 284, 345, 498, 544, 649, 844, 1051, 1171, 1384, 1497, 1514, 1638, 1856, 2860, 2890, 3235, 3584, 4047, 5990 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

n=4: 89=2*2*2+3*3*3*3 is prime.

n=15: 3^15+2^14 = 14365291 is prime.

MATHEMATICA

Do[ If[ PrimeQ[3^n + 2^(n - 1)], Print[n]], {n, 7650}] (from Robert G. Wilson v 24 2004)

CROSSREFS

Cf. A082101, A082102, A095906, A093717, A093793, A093765, A096185, A093794, A093795, A096186.

Sequence in context: A181062 A091199 A093452 * A051602 A175413 A192048

Adjacent sequences:  A082100 A082101 A082102 * A082104 A082105 A082106

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Apr 14 2003

EXTENSIONS

Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), May 25 2004

Edited by N. J. A. Sloane (njas(AT)research.att.com), Sep 15 2008 at the suggestion of R. J. Mathar

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Last modified February 14 11:36 EST 2012. Contains 205623 sequences.