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A073958
Fibonacci numbers for which the number of prime factors (with multiplicity) is a Fibonacci number.
1
1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 233, 377, 610, 987, 1597, 2584, 4181, 10946, 17711, 28657, 75025, 121393, 514229, 1346269, 3524578, 5702887, 9227465, 24157817, 39088169, 63245986, 165580141, 433494437
OFFSET
1,2
COMMENTS
The prime Fibonacci numbers, A005478, are a subsequence.
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..328
EXAMPLE
Example: 8=2*2*2, the number of prime factors is equal to 3, a Fibonacci number.
MATHEMATICA
With[{fibs=Fibonacci[Range[0, 50]]}, Rest[Select[fibs, MemberQ[fibs, PrimeOmega[#]]&]]] (* Harvey P. Dale, Oct 27 2011 *)
PROG
(PARI) isFibonacci(n)=my(k=n^2); k+=((k + 1) << 2); issquare(k) || (n > 0 && issquare(k-8))
select(n->isFibonacci(bigomega(n)), vector(99, i, fibonacci(i+1))) \\ Charles R Greathouse IV, Jun 17 2013
CROSSREFS
Cf. A000045.
Sequence in context: A177372 A109609 A274162 * A074317 A077371 A077372
KEYWORD
nice,nonn
AUTHOR
Felice Russo, Sep 03 2002
STATUS
approved