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A103740 Numbers n such that n! * F(n) + 1 is prime. 0
1, 2, 3, 4, 5, 7, 8, 10, 11, 15, 41, 98, 149, 193, 233, 265, 403, 898, 935, 1291, 2079 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

All values through 2079 have been proved prime with WinPFGW. No more terms up to 6700. Primality testing 2079!*F(2079)+1 [N-1, Brillhart-Lehmer-Selfridge] Running N-1 test using base 2087 Running N-1 test using base 2099 Calling Brillhart-Lehmer-Selfridge with factored part 33.88% 2079!*F(2079)+1 is prime! (15.2535s+0.0043s)

No more terms < 6729. - David Wasserman, Apr 24 2008

LINKS

Table of n, a(n) for n=1..21.

EXAMPLE

a(6)=7 because 7!*fibonacci(7)+1 = 65521, a prime.

CROSSREFS

Cf. A005443.

Sequence in context: A219040 A305414 A317296 * A317578 A306435 A034155

Adjacent sequences:  A103737 A103738 A103739 * A103741 A103742 A103743

KEYWORD

nonn,less

AUTHOR

Jason Earls, Mar 28 2005

STATUS

approved

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Last modified June 20 17:51 EDT 2019. Contains 324234 sequences. (Running on oeis4.)