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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A056353 Number of bracelet structures using a maximum of three different colored beads. 10
1, 2, 3, 6, 9, 22, 40, 100, 225, 582, 1464, 3960, 10585, 29252, 80819, 226530, 636321, 1800562, 5107480, 14548946, 41538916, 118929384, 341187048, 980842804, 2824561089, 8147557742, 23536592235 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Turning over will not create a new bracelet. Permuting the colors of the beads will not change the structure.

REFERENCES

M. R. Nester (1999). Mathematical investigations of some plant interaction designs. PhD Thesis. University of Queensland, Brisbane, Australia. [See A056391 for pdf file of Chap. 2]

LINKS

Table of n, a(n) for n=1..27.

R. M. Thompson and R. T. Downs, Systematic generation of all nonequivalent close-packed stacking sequences..., Acta Cryst. B57 (2001), 766-771; B58 (2002), 153.

FORMULA

Use de Bruijn's generalization of Polya's enumeration theorem as discussed in reference.

CROSSREFS

Cf. A002076, A000011, A027671, A114438.

Sequence in context: A191469 A091053 A095064 * A111274 A133385 A002076

Adjacent sequences:  A056350 A056351 A056352 * A056354 A056355 A056356

KEYWORD

nonn

AUTHOR

Marks R. Nester

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 November 12 12:43 EST 2018. Contains 317109 sequences. (Running on oeis4.)