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%I #22 Apr 05 2023 13:43:06
%S 5,5,7,13,31,73,181,349,859,1723,3361,6091,11833,22273,41959,77713,
%T 138403,249439,447793,799741,1399201,2459923,4312741,7581943,13233841,
%U 23019043,39921979,69112963,119168383,205190353,352286899,603678289,1032646423,1763797501
%N k-th upper twin prime, where k is the n-th Fibonacci number.
%F a(n) = 2 + A093306(n) = A006512(A000045(n)). - _R. J. Mathar_, Feb 06 2010
%t Module[{nn=10^7,fibs,twns},twns=Select[Partition[Prime[Range[nn]],2,1],#[[2]]-#[[1]]==2&][[;;,2]];fibs=Fibonacci[Range[Floor[Log[GoldenRatio,Sqrt[5]Max[Length[twns]]]]]];Table[Take[twns,{f,f}],{f,fibs}]]//Flatten (* _Harvey P. Dale_, Apr 05 2023 *)
%o (PARI) g(n) = for(x=1,n,print1(twinu(fibonacci(x))",")) twinu(n) = { local(c,x); c=0; x=1; while(c<n, if(isprime(prime(x)+2),c++); x++; ); return(prime(x)) }
%o (PARI) default(primelimit, 20000000); twinu(n) = { local(c, x); c=0; x=1; while(c<n, if(isprime(prime(x)+2), c++); x++); return(prime(x)) } { for(n=1, 25, write("b093307.txt", n, " ", twinu(fibonacci(n)))); } \\ _Harry J. Smith_, Jun 20 2009
%Y Cf. A000045, A006512, A093306.
%K nonn
%O 1,1
%A _Cino Hilliard_, Apr 25 2004
%E a(24)-a(25) from _Harry J. Smith_, Jun 20 2009
%E a(26)-a(34) from _Giovanni Resta_, Jun 10 2018
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