login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A273060 a(n) = phi(n!)/phi(n). 1
1, 1, 1, 4, 8, 96, 192, 2304, 13824, 207360, 829440, 24883200, 99532800, 2786918400, 31352832000, 501645312000, 4013162496000, 192631799808000, 1155790798848000, 52010585948160000, 728148203274240000, 19223112566439936000, 192231125664399360000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

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

FORMULA

a(n) = A048855(n)/A000010(n). - Michel Marcus, 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 *)

PROG

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

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

CROSSREFS

Cf. A000010, A048855.

Sequence in context: A057974 A071277 A336795 * A215844 A111100 A105036

Adjacent sequences:  A273057 A273058 A273059 * A273061 A273062 A273063

KEYWORD

nonn

AUTHOR

Alexander R. Povolotsky, Oct 29 2016

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 12 07:28 EDT 2021. Contains 343821 sequences. (Running on oeis4.)