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A197218 a(n) = phi(Lucas(n)). 4

%I

%S 1,1,2,2,6,10,6,28,46,36,80,198,132,520,560,600,2206,3570,1908,9348,

%T 12960,11760,25704,63480,50692,150000,180960,208008,609084,1130304,

%U 604800,3010348,4865280,3920400,8374344,17836000,13685760,54018520,58269200,69600960

%N a(n) = phi(Lucas(n)).

%H Amiram Eldar, <a href="/A197218/b197218.txt">Table of n, a(n) for n = 0..1000</a> (using Blair Kelly's data; terms 0..200 from Vincenzo Librandi)

%H Blair Kelly, <a href="http://mersennus.net/fibonacci//">Fibonacci and Lucas Factorizations</a>

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

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

%o (MAGMA) [EulerPhi(Lucas(n)): n in [0..40]]; // _Vincenzo Librandi_, Oct 13 2011

%o (PARI) for(n=0,30, print1(eulerphi(fibonacc(n+1) + fibonacci(n-1)), ", ")) \\ _G. C. Greubel_, Dec 22 2017

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

%K nonn

%O 0,3

%A _T. D. Noe_, Oct 12 2011

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Last modified January 22 19:16 EST 2020. Contains 331153 sequences. (Running on oeis4.)