login
This site is supported by donations to The OEIS Foundation.

 

Logo

The OEIS is looking to hire part-time people to help edit core sequences, upload scanned documents, process citations, fix broken links, etc. - Neil Sloane, njasloane@gmail.com

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A167748 phi((n!!)!) 0
1, 1, 2, 9216, 250822656000, 1721860898320750629665025350129266874199532634112000000000000, 127571798940158944523056860801259448502131218787316228449430227816121623349001793754442941084615568218917882938952698416464702214493962240000000000000000000000000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Next term has 827 digits.

LINKS

Table of n, a(n) for n=1..7.

MATHEMATICA

Table[EulerPhi[n!!! ], {n, 7}]

CROSSREFS

Sequence in context: A171939 A104904 A272247 * A203755 A285692 A086563

Adjacent sequences:  A167745 A167746 A167747 * A167749 A167750 A167751

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Nov 10 2009

EXTENSIONS

Corrected by Charles R Greathouse IV, Nov 12 2009

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified May 30 00:42 EDT 2017. Contains 287304 sequences.