A178764 Ratio of the primitive part of Fibonacci(n) to the product of primitive prime factors of Fibonacci(n).

1, 1, 1, 1, 1, 4, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 5, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 13, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1

Offset: 1

Author

T. D. Noe, Jun 10 2010

Keywords

• nonn

Comments

Except for a(6), it can be shown that all terms are either 1 or prime. In the first 10^5 terms, only 151 are greater than 1.

Links

• T. D. Noe, Table of n, a(n) for n=1..10000
• Florian Luca, Carl Pomerance, and Stephen Wagner, Fibonacci Integers (preprint)

Formula

a(n) = A061446(n) / A178763(n).