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A117595 Numbers n such that F(2*n - 1) is prime, where F(m) is a Fibonacci number. 3
2, 3, 4, 6, 7, 9, 12, 15, 22, 24, 42, 66, 69, 180, 216, 217, 225, 255, 285, 286, 1486, 2362, 2694, 4656, 4839, 7216, 12781, 15379, 18000, 18756, 25417, 40920, 52456, 65011, 74046, 100554, 198690, 216891, 295021, 296845, 302356 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See A001605, which is the main entry for Fibonacci primes, for the latest information. - N. J. A. Sloane, Jul 09 2016

Or, A001519(n) is prime. - Zak Seidov, Jul 04 2016

LINKS

Table of n, a(n) for n=1..41.

C. Caldwell's FibonacciPrime pages.

H. Dubner and W. Keller, New Fibonacci and Lucas Primes, Math. Comp. 68 (1999) 417-427.

PRP Top Records, Search for: F(n)

FORMULA

2*a(n)-1 = A001605(n+1) for all odd A001605(n+1). - R. J. Mathar, Apr 07 2006

EXAMPLE

If n=69 then F(2*n - 1) is a prime with 29 digits.

MATHEMATICA

Select[Range[2500], PrimeQ[Fibonacci[2# - 1]] &] (* Stefan Steinerberger, Apr 06 2006 *)

PROG

(PARI) { for(n=1, 10000, if ( isprime( fibonacci(2*n-1) ), print1(n, ", "); ); ); } \\ R. J. Mathar, Apr 07 2006

CROSSREFS

Cf. A000045, A001605 (Fibonacci(n) is prime), A001519.

Sequence in context: A018629 A018357 A061489 * A050050 A222801 A117307

Adjacent sequences:  A117592 A117593 A117594 * A117596 A117597 A117598

KEYWORD

nonn

AUTHOR

Parthasarathy Nambi, Apr 05 2006

EXTENSIONS

More terms from Stefan Steinerberger, T. D. Noe and R. J. Mathar, Apr 07 2006

STATUS

approved

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Last modified July 20 11:28 EDT 2019. Contains 325180 sequences. (Running on oeis4.)