A117595 Numbers n such that F(2*n - 1) is prime, where F(m) is a Fibonacci number.

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

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