A075775 Numbers k that divide phi(Fibonacci(k)).

1, 10, 11, 12, 14, 15, 18, 20, 21, 22, 24, 25, 26, 27, 28, 29, 30, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 44, 45, 46, 48, 49, 50, 51, 52, 53, 54, 55, 56, 58, 60, 62, 63, 64, 65, 66, 67, 68, 69, 70, 72, 73, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86, 88, 89, 90, 91, 92, 93

Offset

1,2

Comments

This sequence is infinite (Luca, 2002). - Amiram Eldar, Jan 12 2022

Links

Amiram Eldar, Table of n, a(n) for n = 1..1343

Florian Luca, Problem H-590, Advanced Problems and Solutions, The Fibonacci Quarterly, Vol. 40, No. 5 (2002), p. 472; Arithmetic Functions of Fibonacci Numbers, Solution to Problem H-590 by J.-Ch. Schlage-Puchta and J. Spilker, ibid., Vol. 41, No. 4 (2002), pp. 382-384.

Mathematica

Select[Range[100], Divisible[EulerPhi[Fibonacci[#]], #]&] (* Harvey P. Dale, Jun 11 2015 *)

Crossrefs

Cf. A000010, A000045, A065449.

Sequence in context: A108584 A098605 A126802 * A262393 A031089 A110186

Adjacent sequences: A075772 A075773 A075774 * A075776 A075777 A075778

Keyword

easy,nonn

Author

Benoit Cloitre, Oct 09 2002

Status

approved