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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 (list; graph; refs; listen; history; text; internal format)
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

Adjacent sequences:  A073955 A073956 A073957 * A073959 A073960 A073961

KEYWORD

nice,nonn

AUTHOR

Felice Russo, Sep 03 2002

STATUS

approved

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Last modified February 17 12:32 EST 2020. Contains 331996 sequences. (Running on oeis4.)