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Numbers n such that Fibonacci(n)-Fibonacci(i) is composite for all i=0..n-3.
1

%I #5 Nov 05 2017 08:15:14

%S 14,22,26,30,31,34,38,40,42,44,46,54,61,62,64,65,67,78,80,82,88,92,94,

%T 95,98,102,103,109,112,113,117,119,121,122,125,126,127,134,135,138,

%U 139,142,143,152,154,155,158,166,167,170,172,174,175,176,182,188,190,193

%N Numbers n such that Fibonacci(n)-Fibonacci(i) is composite for all i=0..n-3.

%C These are the n such that A113189(n)=0.

%t lst={}; Do[i=0; While[i<n-2 && !PrimeQ[Fibonacci[n]-Fibonacci[i]], i++ ]; If[i==n-2, AppendTo[lst, n]], {n, 3, 220}]; lst

%t Select[Range[3,200],AllTrue[Fibonacci[#]-Fibonacci[Range[0,#-3]], CompositeQ] &] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Nov 05 2017 *)

%Y Cf. A113188 (primes that are the difference of two Fibonacci numbers).

%K nonn

%O 1,1

%A _T. D. Noe_, Oct 17 2005