OFFSET
1,3
COMMENTS
Prime divisors counted without multiplicity. - Harvey P. Dale, May 25 2020
LINKS
Eric Weisstein's World of Mathematics, Fibonacci Number
Eric Weisstein's World of Mathematics, Lucas Number
EXAMPLE
F(30) + L(30) = 2692538, which has the 3 prime divisors {2, 557, 2417}, so a(30) = 3.
MATHEMATICA
Do[f = Fibonacci[n]; l = Fibonacci[n-1] + Fibonacci[n+1]; Print[Length[FactorInteger[f + l]]], {n, 100}]
Table[PrimeNu[Fibonacci[n]+LucasL[n]], {n, 100}] (* Harvey P. Dale, May 25 2020 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Ryan Propper, Jul 21 2006
EXTENSIONS
Definition clarified by Harvey P. Dale, May 25 2020
STATUS
approved