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A075775
Numbers k that divide phi(Fibonacci(k)).
2
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
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
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Oct 09 2002
STATUS
approved