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Primes p such that the p-th Fibonacci number is composite.
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%I #21 Aug 05 2021 02:31:04

%S 19,31,37,41,53,59,61,67,71,73,79,89,97,101,103,107,109,113,127,139,

%T 149,151,157,163,167,173,179,181,191,193,197,199,211,223,227,229,233,

%U 239,241,251,257,263,269,271,277,281,283,293,307,311,313,317,331,337

%N Primes p such that the p-th Fibonacci number is composite.

%H Hans Havermann, <a href="/A038672/b038672.txt">Table of n, a(n) for n = 1..10000</a>

%H Hans Havermann, <a href="http://chesswanks.com/num/CompositePrimeIndexFibonaccis.txt">Composite Prime-Index Fibonacci Numbers Factored</a>

%t Rest[Select[Prime[Range[68]], ! PrimeQ[Fibonacci[#]] &]] (* _Jayanta Basu_, Jul 10 2013 *)

%t s={A083668}; Complement[Prime[Range[2, 10034]], s] (* _Hans Havermann_, Feb 12 2014 *)

%Y Cf. A090819 (essentially identical), A083668, A135952.

%K nonn

%O 1,1

%A _Jeff Burch_