A168514 Number of prime divisors (counted with multiplicity) of Fibonacci(n)+1.

1, 1, 1, 2, 2, 2, 2, 2, 2, 4, 4, 2, 4, 5, 2, 4, 3, 3, 4, 3, 3, 8, 4, 2, 4, 5, 3, 5, 5, 5, 4, 4, 2, 6, 6, 2, 7, 9, 4, 6, 5, 4, 6, 5, 4, 12, 4, 4, 6, 5, 5, 7, 6, 6, 7, 6, 4, 10, 6, 2, 7, 9, 4, 6, 5, 4, 6, 7, 6, 13, 7, 4, 7, 7, 5, 8, 5, 8, 6, 4, 5, 10, 8, 4, 7, 11, 5, 8, 9, 7, 8, 6, 4, 15, 5, 3, 7, 10, 7, 8, 7, 8

Offset: 1

Author

Jason Earls, Nov 28 2009

Keywords

• nonn

Comments

Always greater than 1 for any n >= 4.

References

• Jason Earls, "Fibonacci," Mathematical Bliss, Pleroma Publications, 2009, pages 60-64. ASIN: B002ACVZ6O

Links

• Amiram Eldar, Table of n, a(n) for n = 1..2803

Crossrefs

Cf. A000045, A001222, A001611.

Programs

Mathematica

Table[PrimeOmega[Fibonacci[n] + 1], {n, 100}] (* Wesley Ivan Hurt, Feb 04 2014 *)

PARI

A168514(n) = bigomega(fibonacci(n)+1) \\ Michael B. Porter, Mar 02 2010

Formula

a(n) = Omega(Fibonacci(n) + 1) = A001222(A001611(n)). - Wesley Ivan Hurt, Feb 04 2014