OFFSET
0,6
EXAMPLE
Fibonacci(7)=13, there are 5 primes less than 13, so a(7)=5.
MATHEMATICA
Table[If[PrimeQ[Fibonacci[n]], PrimePi[Fibonacci[n]-1], PrimePi[ Fibonacci[ n]]], {n, 0, 50}] (* Harvey P. Dale, Feb 12 2022 *)
PROG
(PARI) a(n) = primepi(fibonacci(n)-1) \\ Michel Marcus, May 13 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Alex Ratushnyak, May 05 2012
STATUS
approved