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A273060 a(n) = phi(n!)/phi(n). 1

%I

%S 1,1,1,4,8,96,192,2304,13824,207360,829440,24883200,99532800,

%T 2786918400,31352832000,501645312000,4013162496000,192631799808000,

%U 1155790798848000,52010585948160000,728148203274240000,19223112566439936000,192231125664399360000

%N a(n) = phi(n!)/phi(n).

%H Robert Israel, <a href="/A273060/b273060.txt">Table of n, a(n) for n = 1..450</a>

%F a(n) = A048855(n)/A000010(n). - _Michel Marcus_, Oct 30 2016

%p seq(numtheory:-phi(n!)/numtheory:-phi(n), n=1..50); # _Robert Israel_, Nov 13 2016

%t Table[EulerPhi[n!]/EulerPhi[n], {n,1,25}] (* _G. C. Greubel_, Oct 30 2016 *)

%o (MAGMA) [EulerPhi(Factorial(n)) div EulerPhi(n): n in [1..25]]; // _Vincenzo Librandi_, Oct 30 2016

%o (PARI) a(n) = eulerphi(n!)/eulerphi(n); \\ _Michel Marcus_, Oct 30 2016

%Y Cf. A000010, A048855.

%K nonn

%O 1,4

%A _Alexander R. Povolotsky_, Oct 29 2016

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Last modified June 14 03:38 EDT 2021. Contains 345018 sequences. (Running on oeis4.)