cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A180502 Triangle read by row. T(n,m) gives the number of isomorphism classes of arrangements of n pseudolines and m double pseudolines in the Moebius strip.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 5, 17, 59, 3, 45, 799, 15649, 245351
Offset: 0

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Author

Vincent Pilaud, Sep 08 2010

Keywords

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.

Crossrefs

See A180503 for isomorphism classes of simple arrangements of n pseudolines and m double pseudolines in the Moebius strip.
See A180501 for isomorphism classes of arrangements of n pseudolines and m double pseudolines in the projective plane.
First diagonal gives A063854.