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Smallest Fibonacci numbers with prime indices which have n prime factors.
1

%I #15 Jun 12 2017 15:58:51

%S 2,4181,24157817,83621143489848422977,

%T 322615043836854783580186309282650000354271239929

%N Smallest Fibonacci numbers with prime indices which have n prime factors.

%e a(3) = 24157817 because 24157817 is the smallest Fibonacci number with a prime index (that is, 37) which has 3 prime factors (24157817 = 73*149*2221).

%t Transpose[Flatten[Table[Select[{#, PrimeOmega[#]}&/@Fibonacci[Prime[Range[50]]], Last[#]==n&,1], {n, 5}], 1]][[1]] (* To generate the first 6 terms, change 50 to 100 inside Range and change 5 to 6 for the upper limit of n. *) (* _Harvey P. Dale_, Jun 20 2013 *)

%Y Cf. A114704 (indices), A135958 (indices).

%K hard,nonn

%O 1,1

%A _Shyam Sunder Gupta_, Feb 18 2006

%E Definition and example clarified by _Harvey P. Dale_, Jun 20 2013