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

1, 1, 1, 4, 8, 96, 192, 2304, 13824, 207360, 829440, 24883200, 99532800, 2786918400, 31352832000, 501645312000, 4013162496000, 192631799808000, 1155790798848000, 52010585948160000, 728148203274240000, 19223112566439936000, 192231125664399360000

Offset: 1

Author

Alexander R. Povolotsky, Oct 29 2016

Keywords

• nonn

Links

• Robert Israel, Table of n, a(n) for n = 1..450

Crossrefs

Cf. A000010, A048855.

Programs

Magma

[EulerPhi(Factorial(n)) div EulerPhi(n): n in [1..25]]; // Vincenzo Librandi, Oct 30 2016

Maple

seq(numtheory:-phi(n!)/numtheory:-phi(n), n=1..50); # Robert Israel, Nov 13 2016

Mathematica

Table[EulerPhi[n!]/EulerPhi[n], {n,1,25}] (* G. C. Greubel, Oct 30 2016 *)

PARI

a(n) = eulerphi(n!)/eulerphi(n); \\ Michel Marcus, Oct 30 2016

Formula

a(n) = A048855(n)/A000010(n). - Michel Marcus, Oct 30 2016