%I #2 Mar 31 2012 12:38:16
%S 21,317811,
%T 3254830071569718737604135765141440985245996862858900395844371829572479434062128681271684515666943918276960875482517915520246056253019766319301321652047243019401297415371
%N Numbers n such that if f[n] = n-th Fibonacci number then f[n]-n=prime and f[n]+n=prime.
%t lst={};Do[f=Fibonacci[n];If[PrimeQ[f-n]&&PrimeQ[f+n],AppendTo[lst,f]],{n,7!}];lst
%K nonn,bref
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Aug 30 2008