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A163159
Fibonacci numbers F such that F^2-2 is prime.
0
2, 3, 5, 13, 21, 55, 89, 233, 987, 1597, 5702887, 1836311903, 99194853094755497, 26925748508234281076009, 184551825793033096366333, 468340976726457153752543329995929, 30010821454963453907530667147829489881, 1188518561323126046432205871807859915657177
OFFSET
1,1
COMMENTS
In condensed representation: The A000045(i) at i = 3, 4, 5, 7, 8, 10, 11, 13, 16, 17, 34, 46,... [R. J. Mathar, Jul 25 2009]
FORMULA
{A000045(i): A008865(A000045(i)) in A000040}. [R. J. Mathar, Jul 25 2009]
EXAMPLE
2^2-2=2. 3^2-2=7. 5^2-2=23.
MATHEMATICA
f[n_]:=Fibonacci[n]; f2[n_]:=f[n]^2-2; lst={}; Do[If[PrimeQ[f2[n]], AppendTo[lst, f[n]]], {n, 6!}]; lst
Select[Fibonacci[Range[400]], PrimeQ[#^2-2]&] (* Harvey P. Dale, Oct 21 2011 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Harvey P. Dale, Oct 21 2011
STATUS
approved