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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A208189 Number of distinct n-colored necklaces with 8 beads per color. 2
1, 1, 810, 394397776, 3111284141045598, 191417861328837588057432, 60192781171721237282811209918160, 73288704867601350013562616043249358012160, 283839436431731355577562936415156522873876247241520, 3019803425783983174717206845130801781814711776972408728524160 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..30

FORMULA

a(n) = Sum_{d|8} phi(8/d)*(n*d)!/(d!^n*n*8) if n>0 and a(0) = 1.

EXAMPLE

a(0) =   1: the empty necklace.

a(1) =   1: {00000000}.

a(2) = 810: {0000000011111111, ..., 0101010101010101}.

MAPLE

with(numtheory);

a:= n-> `if`(n=0, 1, add(phi(8/d) *(n*d)!/(d!^n *8*n), d={1, 2, 4, 8})):

seq(a(n), n=0..10);

CROSSREFS

Row n=8 of A208183.

Cf. A000010, A000142.

Sequence in context: A282376 A203844 A068278 * A183216 A093633 A045228

Adjacent sequences:  A208186 A208187 A208188 * A208190 A208191 A208192

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Feb 24 2012

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 March 26 23:02 EDT 2019. Contains 321565 sequences. (Running on oeis4.)