A180503 Triangle read by row. T(n,m) gives the number of isomorphism classes of simple arrangements of n pseudolines and m double pseudolines in the Moebius strip.

1, 1, 1, 1, 1, 1, 1, 3, 7, 16, 2, 13, 140, 1499, 11502, 3, 122, 5589, 245222, 9186477, 238834187

Offset: 0

Author

Vincent Pilaud, Sep 08 2010

Keywords

• nonn
• tabl
• more

References

• J. Ferté, V. Pilaud and M. Pocchiola, On the number of arrangements of five double pseudolines, Abstracts 18th Fall Workshop on Comput. Geom. (FWCG08), Troy, NY, October 2008.

Links

• J. Ferté, V. Pilaud and M. Pocchiola, On the number of simple arrangements of five double pseudolines, arXiv:1009.1575 [cs.CG], 2010; Discrete Comput. Geom. 45 (2011), 279-302.

Crossrefs

See A180502 for isomorphism classes of all (not only simple) arrangements of n pseudolines and m double pseudolines in the Moebius strip.

See A180500 for isomorphism classes of simple arrangements of n pseudolines and m double pseudolines in the projective plane.

First diagonal gives A006247.