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%I #7 Jan 30 2024 15:11:25
%S 1,2,3,4,5,7,8,10,11,15,41,98,149,193,233,265,403,898,935,1291,2079
%N Numbers n such that n! * F(n) + 1 is prime.
%C 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)
%C No more terms < 6729. - _David Wasserman_, Apr 24 2008
%e a(6)=7 because 7!*fibonacci(7)+1 = 65521, a prime.
%t Select[Range[410],PrimeQ[#!Fibonacci[#]+1]&] (* The program generates the first 17 terms of the sequence. *) (* _Harvey P. Dale_, Jan 30 2024 *)
%Y Cf. A005443.
%K nonn,less
%O 1,2
%A _Jason Earls_, Mar 28 2005
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