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a(n) is the number of prime factors in Fibonacci(Prime(n)); that is, the Fibonacci number whose index is the n-th prime.

+0
3

0, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 3, 2, 1, 1, 2, 2, 2, 3, 2, 2, 2, 1, 2, 4, 2, 3, 2, 2, 2, 2, 1, 1, 3, 4, 2, 4, 4, 2, 2, 3, 3, 2, 2, 4, 2, 4, 4, 2, 5, 3, 4, 3, 2, 3, 3, 4, 2, 2, 3, 4, 2, 4, 4, 4, 3, 2, 3, 5, 4, 2, 1, 7, 5, 4, 3, 3, 2, 2, 4, 3, 4, 1, 1, 5, 5, 1, 3, 5, 3, 2, 3, 4, 3, 4, 6, 1, 3, 4, 3 (list; graph; listen)

	OFFSET	`1,8`
	COMMENT	`When a(n)=1, the Fibonacci number is prime and Prime(n) can be found in A001605. Interestingly, the 14 terms a(2) to a(15) match the first 14 terms of A014600, a sequence dealing with the class numbers of imaginary quadratic fields. For n>60, counts were taken from Blair Kelly's website.`
	LINKS	`T. D. Noe, Table of n, a(n) for n=1..168 (using Blair Kelly's data)` `Blair Kelly, Fibonacci and Lucas Factorizations`
	EXAMPLE	`a(12) = 3 because Fibonacci(37) = 24157817 = 73 * 149 * 2221 has 3 prime factors.`
	MATHEMATICA	`Table[Length[FactorInteger[Fibonacci[Prime[n]]]], {n, 60}]`
	CROSSREFS	`Cf. A001605, A014600, A022307.` `Sequence in context: A063740 A072782 A122563 this_sequence A004737 A014600 A098280` `Adjacent sequences: A080342 A080343 A080344 this_sequence A080346 A080347 A080348`
	KEYWORD	`hard,nonn`
	AUTHOR	`T. D. Noe (noe(AT)sspectra.com), Feb 16 2003`

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Last modified November 21 14:49 EST 2008. Contains 150807 sequences.

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