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A076212 Numbers n such that n and Fibonacci(n) have the same number of prime factors. 0
1, 3, 5, 7, 9, 10, 11, 13, 14, 17, 22, 23, 26, 29, 34, 43, 47, 64, 83, 94, 121, 131, 137, 359, 431, 433, 449, 509, 569, 571 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

More precisely, numbers n such that Omega(n) = Omega(Fibonacci(n)), where Omega(n) (A001222) denotes the number of prime factors of n, counting multiplicity.

EXAMPLE

a(6)=9 because 9 and 9th Fibonacci number (i.e. 34) have the same number of prime factors i.e. 2

MAPLE

with(numtheory): with(combinat): a:=proc(n) if bigomega(n)=bigomega(fibonacci(n)) then n else fi end: seq(a(n), n=1..150); - Emeric Deutsch (deutsch(AT)duke.poly.edu), Feb 15 2006

MATHEMATICA

Omega[n_] := Apply[Plus, Transpose[FactorInteger[n]][[2]]]; Flatten[Append[{1}, Select[Range[3, 150], Omega[ # ] == Omega[Fibonacci[ # ]] &]]]

CROSSREFS

Sequence in context: A096849 A080259 A067715 * A085621 A091066 A103848

Adjacent sequences:  A076209 A076210 A076211 * A076213 A076214 A076215

KEYWORD

more,nonn

AUTHOR

Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Nov 03 2002

EXTENSIONS

359 from Harvey P. Dale (hpd1(AT)nyu.edu), May 01 2008

Edited by R. J. Mathar, Aug 11 2008

More terms from D. S. McNeil (mcneil(AT)hku.hk), Dec 23 2010

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Last modified February 16 11:51 EST 2012. Contains 205908 sequences.