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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A063800 Number of nonisomorphic oriented matroids with n points in 2 dimensions. 3
1, 2, 4, 17, 143, 4890, 461053, 95052532 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

REFERENCES

J. Ferte, V. Pilaud and M. Pocchiola, On the number of simple arrangements of five double pseudolines. Discrete Comput. Geom. 45 (2011), 279-302.

Lukas Finschi, A Graph Theoretical Approach for Reconstruction and Generation of Oriented Matroids, A dissertation submitted to the Swiss Federal Institute of Technology, Zurich for the degree of Doctor of Mathematics, 2001.

Fukuda, Komei; Miyata, Hiroyuki; Moriyama, Sonoko. Complete Enumeration of Small Realizable Oriented Matroids. Discrete Comput. Geom. 49 (2013), no. 2, 359--381. MR3017917. - From N. J. A. Sloane, Feb 16 2013

LINKS

Table of n, a(n) for n=3..10.

L. Finschi, Homepage of Oriented Matroids

L. Finschi and K. Fukuda, Complete combinatorial generation of small point set configurations and hyperplane arrangements, pp. 97-100 in Abstracts 13th Canadian Conference on Computational Geometry (CCCG '01), Waterloo, Aug. 13-15, 2001.

CROSSREFS

A diagonal of A063804.

Sequence in context: A307125 A247260 A048872 * A207137 A143674 A136147

Adjacent sequences:  A063797 A063798 A063799 * A063801 A063802 A063803

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Aug 20 2001

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 April 22 06:35 EDT 2019. Contains 322329 sequences. (Running on oeis4.)