A280689 a(n) = A000045(A032742(n)) / A000045(A054576(n)), where A000045(n) gives the n-th Fibonacci number, A032742(n) = the largest proper divisor of n, and A054576(n) = A032742(A032742(n)).

1, 1, 1, 1, 1, 2, 1, 3, 2, 5, 1, 4, 1, 13, 5, 7, 1, 17, 1, 11, 13, 89, 1, 18, 5, 233, 17, 29, 1, 122, 1, 47, 89, 1597, 13, 76, 1, 4181, 233, 123, 1, 842, 1, 199, 122, 28657, 1, 322, 13, 15005, 1597, 521, 1, 5777, 89, 843, 4181, 514229, 1, 1364, 1, 1346269, 842, 2207, 233, 39602, 1, 3571, 28657, 709805, 1, 5778, 1, 24157817, 15005, 9349, 89, 271442, 1, 15127, 5777

Offset

1,6

Comments

A000045 is a divisibility sequence, which guarantees that the result of the division is an integer.

Links

Antti Karttunen, Table of n, a(n) for n = 1..987

Wikipedia, Divisibility sequence

Formula

a(n) = A105800(n) / A280688(n) = A105800(n) / A105800(A032742(n)).

a(n) = A000045(A032742(n)) / A000045(A054576(n)).

a(n) = A280690(A032742(n)).

Prog

(Scheme) (define (A280689 n) (/ (A105800 n) (A280688 n)))

Crossrefs

Cf. A000045, A032742, A054576, A105800, A280688, A280690, A280691.

Sequence in context: A193615 A300383 A120250 * A352961 A116529 A368071

Adjacent sequences: A280686 A280687 A280688 * A280690 A280691 A280692

Keyword

nonn

Author

Antti Karttunen, Jan 11 2017

Status

approved