A197218 a(n) = phi(Lucas(n)).

1, 1, 2, 2, 6, 10, 6, 28, 46, 36, 80, 198, 132, 520, 560, 600, 2206, 3570, 1908, 9348, 12960, 11760, 25704, 63480, 50692, 150000, 180960, 208008, 609084, 1130304, 604800, 3010348, 4865280, 3920400, 8374344, 17836000, 13685760, 54018520, 58269200, 69600960

Offset: 0

Author

T. D. Noe, Oct 12 2011

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 0..1000 (using Blair Kelly's data; terms 0..200 from Vincenzo Librandi)
• Blair Kelly, Fibonacci and Lucas Factorizations

Crossrefs

Cf. A000010, A000032, A065449, A065451, A197219 (Lucas(phi(n))).

Programs

Magma

[EulerPhi(Lucas(n)): n in [0..40]]; // Vincenzo Librandi, Oct 13 2011

Mathematica

Table[EulerPhi[LucasL[n]], {n, 0, 40}]

PARI

for(n=0,30, print1(eulerphi(fibonacci(n+1) + fibonacci(n-1)), ", ")) \\ G. C. Greubel, Dec 22 2017

Formula

a(n) = A000010(A000032(n)).