

A074716


Numbers n such that 2^nF(n) is prime, where F(n) is the nth Fibonacci number.


2



2, 4, 14, 23, 55, 80, 104, 286, 335, 383, 809, 1664, 2096, 2624, 4262, 13544, 14249, 19886, 35500, 40591
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OFFSET

1,1


COMMENTS

1664 and above are pseudoprimes only.  Sam Handler (sam_5_5_5_0(AT)yahoo.com), Dec 26 2004
1664, 2096, 2624 and 4262 correspond to certified primes. (Primo 2.2.0 beta)  Ryan Propper, Aug 29 2005


LINKS

Table of n, a(n) for n=1..20.


MATHEMATICA

Do[ If[ PrimeQ[ 2^n  Fibonacci[n]], Print[n]], {n, 1, 5000}]


CROSSREFS

Cf. A074824.
Sequence in context: A111871 A291079 A090808 * A283290 A283379 A090889
Adjacent sequences: A074713 A074714 A074715 * A074717 A074718 A074719


KEYWORD

more,nonn


AUTHOR

Benoit Cloitre, Sep 04 2002


EXTENSIONS

Edited by Robert G. Wilson v, Sep 06 2002
5 more terms from Sam Handler (sam_5_5_5_0(AT)yahoo.com), Dec 18 2004


STATUS

approved



