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%I #18 Aug 16 2019 14:02:23
%S 0,1,3,8,21,34,55,144,377,610,987,2584,6765,10946,17711,46368,75025,
%T 121393,196418,317811,832040,2178309,3524578,5702887,9227465,14930352,
%U 39088169,63245986,102334155,267914296,701408733,1134903170,1836311903
%N Fibonacci numbers with nonprime indices.
%e 55 is included because 55 is the 10th Fibonacci number and 10 is composite.
%p with(combinat): a:=proc(n) if isprime(n)=false then fibonacci(n) else fi end: seq(a(n),n=0..52); # _Emeric Deutsch_, Oct 04 2005
%t Fibonacci /@ Select[Range[0, 46], ! PrimeQ[ # ] &] (* _Robert G. Wilson v_ *)
%t Module[{nn=50,ix},ix=Table[If[PrimeQ[n],0,1],{n,0,nn}];Pick[Fibonacci[ Range[ 0,nn]],ix,1]] (* _Harvey P. Dale_, Apr 26 2018 *)
%Y Cf. A000045, A018252, A090206.
%K nonn
%O 0,3
%A _Leroy Quet_, Oct 01 2005
%E More terms from _Robert G. Wilson v_ and _Emeric Deutsch_, Oct 04 2005