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 A038575 Number of prime factors of n-th Fibonacci number, counted with multiplicity. 17
 0, 0, 0, 1, 1, 1, 3, 1, 2, 2, 2, 1, 6, 1, 2, 3, 3, 1, 5, 2, 4, 3, 2, 1, 9, 3, 2, 4, 4, 1, 7, 2, 4, 3, 2, 3, 10, 3, 3, 3, 6, 2, 7, 1, 5, 5, 3, 1, 12, 3, 6, 3, 4, 2, 8, 4, 7, 5, 3, 2, 12, 2, 3, 5, 6, 3, 7, 3, 5, 5, 7, 2, 14, 2, 4, 6, 5, 4, 8, 2, 9, 7, 3, 1, 13, 4, 3, 4, 9, 2, 12, 5, 6, 4, 2, 6, 16, 4, 5, 6, 10, 2, 8 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,7 COMMENTS Row lengths of table A060441. - Reinhard Zumkeller, Aug 30 2014 LINKS Amiram Eldar, Table of n, a(n) for n = 0..1408 (terms 0..1000 from T. D. Noe derived from Kelly's data) Blair Kelly, Fibonacci and Lucas Factorizations Eric Weisstein's World of Mathematics, Fibonacci Number FORMULA For n > 0: a(n) = A001222(A000045(n)). - Reinhard Zumkeller, Aug 30 2014 EXAMPLE a(12) = 6 because Fibonacci(12) = 144 = 2^4 * 3^2 has 6 prime factors. MAPLE with(numtheory):with(combinat):a:=proc(n) if n=0 then 0 else bigomega(fibonacci(n)) fi end: seq(a(n), n=0..102); # Zerinvary Lajos, Apr 11 2008 MATHEMATICA Join[{0, 0}, Table[Plus@@(Transpose[FactorInteger[Fibonacci[n]]][[2]]), {n, 3, 102}]] Join[{0}, PrimeOmega[Fibonacci[Range[110]]]] (* Harvey P. Dale, Apr 14 2018 *) PROG (Haskell) a038575 n = if n == 0 then 0 else a001222 \$ a000045 n -- Reinhard Zumkeller, Aug 30 2014 (PARI) a(n)=bigomega(fibonacci(n)) \\ Charles R Greathouse IV, Sep 14 2015 CROSSREFS Cf. A022307 (number of distinct prime factors), A086597 (number of primitive prime factors). Cf. also A001222, A000045, A060441. Sequence in context: A236172 A139381 A225849 * A304302 A305516 A305182 Adjacent sequences:  A038572 A038573 A038574 * A038576 A038577 A038578 KEYWORD nonn AUTHOR STATUS approved

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Last modified November 26 22:26 EST 2020. Contains 338652 sequences. (Running on oeis4.)